Germanium: Difference between revisions

Latest revision as of 08:48, 16 November 2025

Template:Short description Script error: No such module "Distinguish". Template:Pp-move Template:Infobox germanium Germanium is a chemical element; it has symbol Ge and atomic number 32. It is lustrous, hard-brittle, grayish-white and similar in appearance to silicon. It is a metalloid or a nonmetal in the carbon group that is chemically similar to silicon. Like silicon, germanium naturally reacts and forms complexes with oxygen in nature.

Because it seldom appears in high concentration, germanium was found comparatively late in the discovery of the elements. Germanium ranks 50th in abundance of the elements in the Earth's crust. In 1869, Dmitri Mendeleev predicted its existence and some of its properties from its position on his periodic table, and called the element ekasilicon. On February 6, 1886, Clemens Winkler at Freiberg University found the new element, along with silver and sulfur, in the mineral argyrodite. Winkler named the element after Germany, his country of birth. Germanium is mined primarily from sphalerite (the primary ore of zinc), though germanium is also recovered commercially from silver, lead, and copper ores.

Elemental germanium is used as a semiconductor in transistors and various other electronic devices. Historically, the first decade of semiconductor electronics was based entirely on germanium. Presently, the major end uses are fibre-optic systems, infrared optics, solar cell applications, and light-emitting diodes (LEDs). Germanium compounds are also used for polymerization catalysts and have most recently found use in the production of nanowires. This element forms a large number of organogermanium compounds, such as tetraethylgermanium, useful in organometallic chemistry.

Germanium is not thought to be an essential element for any living organism. Similar to silicon and aluminium, naturally occurring germanium compounds tend to be insoluble in water and thus have little oral toxicity. However, synthetic soluble germanium salts are nephrotoxic, and synthetic chemically reactive germanium compounds with halogens and hydrogen are irritants and toxins.

History

File:Mendeleev 1869 prediction of germanium (detail).svg

Prediction of germanium, "?=70" (periodic table 1869)

In his report on The Periodic Law of the Chemical Elements in 1869, the Russian chemist Dmitri Mendeleev predicted the existence of several unknown chemical elements, including one that would fill a gap in the carbon family, located between silicon and tin.^[1] Because of its position in his periodic table, Mendeleev called it ekasilicon (Es), and he estimated its atomic weight to be 70 (later 72).

In mid-1885, at a mine near Freiberg, Saxony, a new mineral was discovered and named argyrodite because of its high silver content.Template:NoteTag The chemist Clemens Winkler analyzed this new mineral, which proved to be a combination of silver, sulfur, and a new element. Winkler was able to isolate the new element in 1886 and found it similar to antimony. He initially considered the new element to be eka-antimony, but was soon convinced that it was instead eka-silicon.^[2]^[3] Before Winkler published his results on the new element, he decided that he would name his element neptunium, since the recent discovery of planet Neptune in 1846 had similarly been preceded by mathematical predictions of its existence.Template:NoteTag However, the name "neptunium" had already been given to another proposed chemical element (though not the element that today bears the name neptunium, which was discovered in 1940).Template:NoteTag So instead, Winkler named the new element germanium (from the Latin word, Germania, for Germany) in honor of his homeland.^[3] Argyrodite proved empirically to be Ag₈GeS₆. Because this new element showed some similarities with the elements arsenic and antimony, its proper place in the periodic table was under consideration, but its similarities with Dmitri Mendeleev's predicted element "ekasilicon" confirmed that place on the periodic table.^[3]^[4] With further material from 500 kg of ore from the mines in Saxony, Winkler confirmed the chemical properties of the new element in 1887.^[2]^[3]^[5] He also determined an atomic weight of 72.32 by analyzing pure germanium tetrachloride (Template:Chem), while Lecoq de Boisbaudran deduced 72.3 by a comparison of the lines in the spark spectrum of the element.^[6]

Winkler was able to prepare several new compounds of germanium, including fluorides, chlorides, sulfides, dioxide, and tetraethylgermane (Ge(C₂H₅)₄), the first organogermane.^[2] The physical data from those compounds—which corresponded well with Mendeleev's predictions—made the discovery an important confirmation of Mendeleev's idea of element periodicity. Here is a comparison between the prediction and Winkler's data:^[2]

Property	Ekasilicon Template:Nobold	Germanium Template:Nobold
atomic mass	72.64	72.63
density (g/cm³)	5.5	5.35
melting point (°C)	high	947
color	gray	gray
oxide type	refractory dioxide	refractory dioxide
oxide density (g/cm³)	4.7	4.7
oxide activity	feebly basic	feebly basic
chloride boiling point (°C)	under 100	86 (GeCl₄)
chloride density (g/cm³)	1.9	1.9

Until the late 1930s, germanium was thought to be a poorly conducting metal.^[7] Germanium did not become economically significant until after 1945 when its properties as an electronic semiconductor were recognized. During World War II, small amounts of germanium were used in some special electronic devices, mostly diodes.^[8]^[9] The first major use was the point-contact Schottky diodes for radar pulse detection during the War.^[7] The first silicon–germanium alloys were obtained in 1955.^[10] Before 1945, only a few hundred kilograms of germanium were produced in smelters each year, but by the end of the 1950s, the annual worldwide production had reached Template:Convert.^[11]

The development of the germanium transistor in 1948^[12] opened the door to countless applications of solid state electronics.^[13] From 1950 through the early 1970s, this area provided an increasing market for germanium, but then high-purity silicon began replacing germanium in transistors, diodes, and rectifiers.^[14] For example, the company that became Fairchild Semiconductor was founded in 1957 with the express purpose of producing silicon transistors. Silicon has superior electrical properties, but it requires much greater purity that could not be commercially achieved in the early years of semiconductor electronics.^[15]

Meanwhile, the demand for germanium for fiber optic communication networks, infrared night vision systems, and polymerization catalysts increased dramatically.^[11] These end uses represented 85% of worldwide germanium consumption in 2000.^[14] The US government even designated germanium as a strategic and critical material, calling for a 146 ton (132 tonne) supply in the national defense stockpile in 1987.^[11]

Germanium differs from silicon in that the supply is limited by the availability of exploitable sources, while the supply of silicon is limited only by production capacity since silicon comes from ordinary sand and quartz. While silicon could be bought in 1998 for less than $10 per kg,^[11] the price of germanium was almost $800 per kg.^[11]

Characteristics

Under standard conditions, germanium is a brittle, silvery-white,^[16] semiconductor. This form constitutes an allotrope known as α-germanium, which has a metallic luster and a diamond cubic crystal structure, the same structure as silicon and diamond.^[14] In this form, germanium has a threshold displacement energy of $19 . 7_{- 0.5}^{+ 0.6} eV$ .^[17] At pressures above 120 kbar, germanium becomes the metallic allotrope β-germanium with the same structure as β-tin.^[18] Like silicon, gallium, bismuth, antimony, and water, germanium is one of the few substances that expands as it solidifies (i.e. freezes) from the molten state.^[18]

Germanium is a semiconductor having an indirect bandgap, as is crystalline silicon. Zone refining techniques have led to the production of crystalline germanium for semiconductors that has an impurity of only one part in 10¹⁰,^[19] making it one of the purest materials ever obtained.^[20] The first semi-metallic material discovered (in 2005) to become a superconductor in the presence of an extremely strong electromagnetic field was an alloy of germanium, uranium, and rhodium.^[21]

Pure germanium is known to spontaneously extrude very long screw dislocations, referred to as germanium whiskers. The growth of these whiskers is one of the primary reasons for the failure of older diodes and transistors made from germanium, as, depending on what they eventually touch, they may lead to an electrical short.^[22]

Chemistry

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Elemental germanium starts to oxidize slowly in air at around 250 °C, forming GeO₂ .^[23] Germanium is insoluble in dilute acids and alkalis but dissolves slowly in hot concentrated sulfuric and nitric acids and reacts violently with molten alkalis to produce germanates (Template:Chem). Germanium occurs mostly in the oxidation state +4 although many +2 compounds are known.^[24] Other oxidation states are rare: +3 is found in compounds such as Ge₂Cl₆, and +3 and +1 are found on the surface of oxides,^[25] or negative oxidation states in germanides, such as −4 in Template:Chem. Germanium cluster anions (Zintl ions) such as Ge₄²⁻, Ge₉⁴⁻, Ge₉²⁻, [(Ge₉)₂]⁶⁻ have been prepared by the extraction from alloys containing alkali metals and germanium in liquid ammonia in the presence of ethylenediamine or a cryptand.^[24]^[26] The oxidation states of the element in these ions are not integers—similar to the ozonides O₃⁻.

Two oxides of germanium are known: germanium dioxide (Template:Chem, germania) and germanium monoxide, (Template:Chem).^[18] The dioxide, GeO₂, can be obtained by roasting germanium disulfide (Template:Chem), and is a white powder that is only slightly soluble in water but reacts with alkalis to form germanates.^[18] The monoxide, germanous oxide, can be obtained by the high temperature reaction of GeO₂ with elemental Ge.^[18] The dioxide (and the related oxides and germanates) exhibits the unusual property of having a high refractive index for visible light, but transparency to infrared light.^[27]^[28] Bismuth germanate, Bi₄Ge₃O₁₂ (BGO), is used as a scintillator.^[29]

Binary compounds with other chalcogens are also known, such as the disulfide (Template:Chem) and diselenide (Template:Chem), and the monosulfide (GeS), monoselenide (GeSe), and monotelluride (GeTe).^[24] GeS₂ forms as a white precipitate when hydrogen sulfide is passed through strongly acid solutions containing Ge(IV).^[24] The disulfide is appreciably soluble in water and in solutions of caustic alkalis or alkaline sulfides. Nevertheless, it is not soluble in acidic water, which allowed Winkler to discover the element.^[30] By heating the disulfide in a current of hydrogen, the monosulfide (GeS) is formed, which sublimes in thin plates of a dark color and metallic luster, and is soluble in solutions of the caustic alkalis.^[18] Upon melting with alkaline carbonates and sulfur, germanium compounds form salts known as thiogermanates.^[31]

Skeletal chemical structure of a tetrahedral molecule with germanium atom in its center bonded to four hydrogen atoms. The Ge–H distance is 152.51 picometers.

Germane is similar to methane.

Four tetrahalides are known. Under normal conditions germanium tetraiodide (GeI₄) is a solid, germanium tetrafluoride (GeF₄) a gas and the others volatile liquids. For example, germanium tetrachloride, GeCl₄, is obtained as a colorless fuming liquid boiling at 83.1 °C by heating the metal with chlorine.^[18] All the tetrahalides are readily hydrolyzed to hydrated germanium dioxide.^[18] GeCl₄ is used in the production of organogermanium compounds.^[24] All four dihalides are known and in contrast to the tetrahalides are polymeric solids.^[24] Additionally Ge₂Cl₆ and some higher compounds of formula Ge_nCl_2n+2 are known.^[18] The unusual compound Ge₆Cl₁₆ has been prepared that contains the Ge₅Cl₁₂ unit with a neopentane structure.^[32]

Germane (GeH₄) is a compound similar in structure to methane. Polygermanes—compounds that are similar to alkanes—with formula Ge_nH_2n+2 containing up to five germanium atoms are known.^[24] The germanes are less volatile and less reactive than their corresponding silicon analogues.^[24] GeH₄ reacts with alkali metals in liquid ammonia to form white crystalline MGeH₃ which contain the GeH₃⁻ anion.^[24] The germanium hydrohalides with one, two and three halogen atoms are colorless reactive liquids.^[24]

Skeletal chemical structures outlining an additive chemical reaction including an organogermanium compound.

Nucleophilic addition with an organogermanium compound

The first organogermanium compound was synthesized by Winkler in 1887; the reaction of germanium tetrachloride with diethylzinc yielded tetraethylgermane (Template:Chem).^[2] Organogermanes of the type R₄Ge (where R is an alkyl) such as tetramethylgermane (Template:Chem) and tetraethylgermane are accessed through the cheapest available germanium precursor germanium tetrachloride and alkyl nucleophiles. Organic germanium hydrides such as isobutylgermane (Template:Chem) were found to be less hazardous and may be used as a liquid substitute for toxic germane gas in semiconductor applications. Many germanium reactive intermediates are known: germyl free radicals, germylenes (similar to carbenes), and germynes (similar to carbynes).^[33]^[34] The organogermanium compound 2-carboxyethylgermasesquioxane was first reported in the 1970s, and for a while was used as a dietary supplement and thought to possibly have anti-tumor qualities.^[35]

Using a ligand called Eind (1,1,3,3,5,5,7,7-octaethyl-s-hydrindacen-4-yl) germanium is able to form a double bond with oxygen (germanone). Germanium hydride and germanium tetrahydride are very flammable and even explosive when mixed with air.^[36]

Isotopes

Script error: No such module "Labelled list hatnote". Germanium occurs in five natural isotopes: Template:SimpleNuclide, Template:SimpleNuclide, Template:SimpleNuclide, Template:SimpleNuclide, and Template:SimpleNuclide. Of these, Template:SimpleNuclide is very slightly radioactive, undergoing double beta decay with a half-life of Template:Val.^[37] Template:SimpleNuclide is the most common isotope, having a natural abundance of 36.52% and Template:SimpleNuclide is the least common with a natural abundance of 7.75%.^[38]

Apart from Template:SimpleNuclide, at least 27 other radioisotopes have been synthesized, ranging in atomic mass from 58 to 89. The most stable of these is Template:SimpleNuclide, decaying by electron capture with a half-life of Template:Val. This is followed by Template:SimpleNuclide, also decaying by electron capture with half-life Template:Val,^[39] and the rest are all less than two days, most under two hours.^[38]

Occurrence

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A brown block of irregular shape and surface, about 6 cm in size.

Renierite

Germanium is created by stellar nucleosynthesis, mostly by the s-process in asymptotic giant branch stars. The s-process is a slow neutron capture of lighter elements inside pulsating red giant stars.^[40] Germanium has been detected in some of the most distant stars^[41] and in the atmosphere of Jupiter.^[42]

Germanium's abundance in the Earth's crust is approximately 1.6 ppm.^[43] Only a few minerals like argyrodite, briartite, germanite, renierite and sphalerite contain appreciable amounts of germanium.^[14]^[44] Only few of them (especially germanite) are, very rarely, found in mineable amounts.^[45]^[46]^[47] Some zinc–copper–lead ore bodies contain enough germanium to justify extraction from the final ore concentrate.^[43] An unusual natural enrichment process causes a high content of germanium in some coal seams, discovered by Victor Moritz Goldschmidt during a broad survey for germanium deposits.^[48]^[49] The highest concentration ever found was in Hartley coal ash with as much as 1.6% germanium.^[48]^[49] The coal deposits near Xilinhaote, Inner Mongolia, contain an estimated 1600 tonnes of germanium.^[43]

Production

About 118 tonnes of germanium were produced in 2011 worldwide, mostly in China (80 t), Russia (5 t) and United States (3 t).^[14] Germanium is recovered as a by-product from sphalerite zinc ores where it is concentrated in amounts as great as 0.3%,^[50] especially from low-temperature sediment-hosted, massive Zn–Pb–Cu(–Ba) deposits and carbonate-hosted Zn–Pb deposits.^[51] A recent study found that at least 10,000 t of extractable germanium is contained in known zinc reserves, particularly those hosted by Mississippi-Valley type deposits, while at least 112,000 t will be found in coal reserves.^[52] In 2007 35% of the demand was met by recycled germanium.^[43]

Year	Cost ($/kg)^[53]
1999	1,400
2000	1,250
2001	890
2002	620
2003	380
2004	600
2005	660
2006	880
2007	1,240
2008	1,490
2009	950
2010	940
2011	1,625
2012	1,680
2013	1,875
2014	1,900
2015	1,760
2016	950
2017	1,358
2018	1,300
2019	1,240
2020	1,000

While it is produced mainly from sphalerite, it is also found in silver, lead, and copper ores. Another source of germanium is fly ash of power plants fueled from coal deposits that contain germanium. Russia and China used this as a source for germanium.^[54] Russia's deposits are located in the far east of Sakhalin Island, and northeast of Vladivostok. The deposits in China are located mainly in the lignite mines near Lincang, Yunnan; coal is also mined near Xilinhaote, Inner Mongolia.^[43]

The ore concentrates are mostly sulfidic; they are converted to the oxides by heating under air in a process known as roasting:

GeS₂ + 3 O₂ → GeO₂ + 2 SO₂

Some of the germanium is left in the dust produced, while the rest is converted to germanates, which are then leached (together with zinc) from the cinder by sulfuric acid. After neutralization, only the zinc stays in solution while germanium and other metals precipitate. After removing some of the zinc in the precipitate by the Waelz process, the residing Waelz oxide is leached a second time. The dioxide is obtained as precipitate and converted with chlorine gas or hydrochloric acid to germanium tetrachloride, which has a low boiling point and can be isolated by distillation:^[54]

GeO₂ + 4 HCl → GeCl₄ + 2 H₂O

GeO₂ + 2 Cl₂ → GeCl₄ + O₂

Germanium tetrachloride is either hydrolyzed to the oxide (GeO₂) or purified by fractional distillation and then hydrolyzed.^[54] The highly pure GeO₂ is now suitable for the production of germanium glass. It is reduced to the element by reacting it with hydrogen, producing germanium suitable for infrared optics and semiconductor production:

GeO₂ + 2 H₂ → Ge + 2 H₂O

The germanium for steel production and other industrial processes is normally reduced using carbon:^[55]

GeO₂ + C → Ge + CO₂

Production by country

World refinery production of germanium (germanium content).

World refinery production / total supply (USGS), with country groups where available
Year	China (t)	Canada (t)	Russia (t)	Other (t)	U.S. refinery (t)	World total (t)	Comment	Source
1970					~15	~85		^[56]
1980			14		27	~115	USSR 14 (est.), Japan 13 t, France 10, Austria 5. Significant recovery also believed in Belgium, China, FRG, Italy.	^[57]^[56]
1990	10	-	12		18	~80	USSR 12 t, Japan 3 t, Austria 5 t	^[58]^[56]
1996					18	71.5	World total market supply ≈71.5 t (≈53 t primary refinery + 12 t recycling + 6.5 t stock releases)	^[59]
1999					20	91	World total market supply (58 t primary refinery + 25 t recycling + 8 t stock releases)	^[60]
2000					23	105	World total market supply (slightly >70 t primary refinery + 25 t recycling + 9 t stock releases)	^[61]
2001					20	110	World total market supply (~<70 t primary refinery + 30 t recycling + 12 t stock releases)	^[62]
2002					12	80	World total market supply (50 t primary refinery + 30 t recycling)	^[63]
2003					12	80	World total market supply (50 t primary refinery + 30 t recycling) - "Starting in 2001, there had been a growing surplus of germanium owing to a major downturn in the fiber optics market. By yearend 2003, supply and demand were in close balance"	^[64]
2004					4.4	87	World total market supply (50 t primary refinery + 30 t recycling + 7 t stock releases)	^[56]
2005					4.5	90	World total market supply (including 31 t recycling)	^[65]
2006					4.6	100	World total market supply (including 35 t recycling). "In 2006, production decreased, while consumption strongly rose, resulting in a deficit. Prices of germanium metal and germanium dioxide in 2007 had increased to record levels"	^[66]
2007					4.6	145	Including 6,902 kg released from the NDS. The recycling supplied about 30% of the world's total	^[67]
2008	~100	~27	~5	~2	4.6	~140	Worldwide, the vast majority of germanium production was concentrated in Canada and China	^[68]^[69]
2009	~100	~27	~5	~2	~6	100 - 120	Worldwide, primary germanium was recovered from copper or zinc residues or from coal in Canada (concentrates shipped from the United States), China (multiple sources), Finland (concentrates from Congo Kinshasa), and Russia (lignite coal from Sakhalin)	^[70]^[69]
2010	~77	~15	~4	~15	9.3	100 - 120	Other is mainly Finland	^[71]^[69]
2013	~107	~20	~4	~21	~4	~155	Other is mainly Finland	^[72]^[69]
2017	79.1	~35	5.0	~1	~4	124		^[73]^[69]
2020	95 - 105	~24	5.0	~3	~2	140		^[73]^[69]
2023	~200	~27	~7	~3	~2	243	"These estimates include both primary and secondary production."	^[69]

Applications

Template:Pie chart

The major global end uses for germanium were electronics and solar applications, fiber-optic systems, infrared optics, and polymerization catalysts. Other uses included chemotherapy, metallurgy, and phosphors.^[74]

Optics

A drawing of four concentric cylinders.

A typical single-mode optical fiber. Germanium oxide is a dopant of the core silica (Item 1). Template:Olist

The notable properties of germania (GeO₂) are its high index of refraction and its low optical dispersion. These make it especially useful for wide-angle camera lenses, microscopy, and the core part of optical fibers.^[75]^[76] It has replaced titania as the dopant for silica fiber, eliminating the subsequent heat treatment that made the fibers brittle.^[77] At the end of 2002, the fiber optics industry consumed 60% of the annual germanium use in the United States, but this is less than 10% of worldwide consumption.^[76] GeSbTe is a phase change material used for its optic properties, such as that used in rewritable DVDs.^[78]

Because germanium is transparent in the infrared wavelengths, it is an important infrared optical material that can be readily cut and polished into lenses and windows. It is especially used as the front optic in thermal imaging cameras working in the 8 to 14 micron range for passive thermal imaging and for hot-spot detection in military, mobile night vision, and fire fighting applications.^[55] It is used in infrared spectroscopes and other optical equipment that require extremely sensitive infrared detectors.^[76] It has a very high refractive index (4.0) and must be coated with anti-reflection agents. Particularly, a very hard special antireflection coating of diamond-like carbon (DLC), refractive index 2.0, is a good match and produces a diamond-hard surface that can withstand much environmental abuse.^[79]^[80]

Electronics

Germanium can be alloyed with silicon, and silicon–germanium alloys are rapidly becoming an important semiconductor material for high-speed integrated circuits. Circuits using the properties of Si-SiGe heterojunctions can be much faster than those using silicon alone.^[81] The SiGe chips, with high-speed properties, can be made with low-cost, well-established production techniques of the silicon chip industry.^[14]

High efficiency solar panels are a major use of germanium. Because germanium and gallium arsenide have nearly identical lattice constant, germanium substrates can be used to make gallium-arsenide solar cells.^[82] Germanium is the substrate of the wafers for high-efficiency multijunction photovoltaic cells for space applications, such as the Mars Exploration Rovers, which use triple-junction gallium arsenide on germanium cells.^[83] High-brightness LEDs, used for automobile headlights and to backlight LCD screens, are also an important application.^[14]

Germanium-on-insulator (GeOI) substrates are seen as a potential replacement for silicon on miniaturized chips.^[14] CMOS circuit based on GeOI substrates has been reported recently.^[84] Other uses in electronics include phosphors in fluorescent lamps^[19] and solid-state light-emitting diodes (LEDs).^[14] Germanium transistors are still used in some effects pedals by musicians who wish to reproduce the distinctive tonal character of the "fuzz"-tone from the early rock and roll era, most notably the Dallas Arbiter Fuzz Face.^[85]

Germanium has been studied as a potential material for implantable bioelectronic sensors that are resorbed in the body without generating harmful hydrogen gas, replacing zinc oxide- and indium gallium zinc oxide-based implementations.^[86]

Germanium was also used to create many of the circuits found in some of the very first pieces of electronic musical gear, initially 1950s, primarily in early transistor-based circuits. The first guitar effects pedals in the 1960s – Fuzz pedals like the Maestro FZ-1 (1962), Dallas-Arbiter Fuzz Face (1966), and Tone Bender (1965) - used germanium transistors.^[87] Silicon diodes are more frequently used in more modern equipment, but germanium diodes are still used in some applications as they have lower barrier potential and smoother transconductance curves, leading to less harsh clipping.^[88]

Other uses

Photo of a standard transparent plastic bottle.

A PET bottle

Germanium dioxide is also used in catalysts for polymerization in the production of polyethylene terephthalate (PET).^[89] The high brilliance of this polyester is especially favored for PET bottles marketed in Japan.^[89] In the United States, germanium is not used for polymerization catalysts.^[14]

Due to the similarity between silica (SiO₂) and germanium dioxide (GeO₂), the silica stationary phase in some gas chromatography columns can be replaced by GeO₂.^[90]

In recent years germanium has seen increasing use in precious metal alloys. In sterling silver alloys, for instance, it reduces firescale, increases tarnish resistance, and improves precipitation hardening. A tarnish-proof silver alloy trademarked Argentium contains 1.2% germanium.^[14]

Semiconductor detectors made of single crystal high-purity germanium can precisely identify radiation sources—for example in airport security.^[91] Germanium is useful for monochromators for beamlines used in single crystal neutron scattering and synchrotron X-ray diffraction. The reflectivity has advantages over silicon in neutron and high energy X-ray applications.^[92] Crystals of high purity germanium are used in detectors for gamma spectroscopy and the search for dark matter.^[93] Germanium crystals are also used in X-ray spectrometers for the determination of phosphorus, chlorine and sulfur.^[94]

Germanium is emerging as an important material for spintronics and spin-based quantum computing applications. In 2010, researchers demonstrated room temperature spin transport^[95] and more recently donor electron spins in germanium has been shown to have very long coherence times.^[96]

Germanium and health

Germanium is not considered essential to the health of plants or animals.^[97] Germanium in the environment has little or no health impact. This is primarily because it usually occurs only as a trace element in ores and carbonaceous materials, and the various industrial and electronic applications involve very small quantities that are not likely to be ingested.^[14] For similar reasons, end-use germanium has little impact on the environment as a biohazard. Some reactive intermediate compounds of germanium are poisonous (see precautions, below).^[98]

Germanium supplements, made from both organic and inorganic germanium, have been marketed as an alternative medicine capable of treating leukemia and lung cancer.^[11] There is, however, no medical evidence of benefit; some evidence suggests that such supplements are actively harmful.^[97] U.S. Food and Drug Administration (FDA) research has concluded that inorganic germanium, when used as a nutritional supplement, "presents potential human health hazard".^[35]

Some germanium compounds have been administered by alternative medical practitioners as non-FDA-allowed injectable solutions. Soluble inorganic forms of germanium used at first, notably the citrate-lactate salt, resulted in some cases of renal dysfunction, hepatic steatosis, and peripheral neuropathy in individuals using them over a long term. Plasma and urine germanium concentrations in these individuals, several of whom died, were several orders of magnitude greater than endogenous levels. A more recent organic form, beta-carboxyethylgermanium sesquioxide (propagermanium), has not exhibited the same spectrum of toxic effects.^[99]

Certain compounds of germanium have low toxicity to mammals, but have toxic effects against certain bacteria.^[16]

Precautions for chemically reactive germanium compounds

While use of germanium itself does not require precautions, some of germanium's artificially produced compounds are quite reactive and present an immediate hazard to human health on exposure. For example, Germanium tetrachloride and germane (GeH₄) are a liquid and gas, respectively, that can be very irritating to the eyes, skin, lungs, and throat.^[100]

Notes

Template:NoteFoot

References

Template:Reflist

External links

Template:Sister project

Germanium at The Periodic Table of Videos (University of Nottingham)
usgs.gov (Mineral Commodity Summaries 2025): Germanium

Template:Subject bar Template:Periodic table (navbox) Template:Germanium compounds Template:Main other

Template:Authority control

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↑ Eugene P. Bertin (1970). Principles and practice of X-ray spectrometric analysis, Chapter 5.4 – Analyzer crystals, Table 5.1, p. 123; Plenum Press
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@@ Line 9: / Line 9: @@
 Elemental germanium is used as a semiconductor in [[transistor]]s and various other electronic devices. Historically, the first decade of semiconductor electronics was based entirely on germanium. Presently, the major end uses are [[fibre-optic]] systems, [[Night-vision device|infrared optics]], [[solar cell]] applications, and [[light-emitting diode]]s (LEDs). Germanium compounds are also used for [[polymerization]] catalysts and have most recently found use in the production of [[nanowire]]s. This element forms a large number of [[organogermanium compound]]s, such as [[tetraethylgermanium]], useful in [[organometallic chemistry]].
-Germanium is not thought to be an essential element for any [[Organic chemistry|living organism]]. Similar to silicon and aluminium, naturally-occurring germanium compounds tend to be insoluble in water and thus have little oral [[toxicity]]. However, synthetic soluble germanium salts are [[nephrotoxic]], and synthetic chemically reactive germanium compounds with [[halogen]]s and [[hydrogen]] are irritants and toxins.
+Germanium is not thought to be an essential element for any [[Organic chemistry|living organism]]. Similar to silicon and aluminium, naturally occurring germanium compounds tend to be insoluble in water and thus have little oral [[toxicity]]. However, synthetic soluble germanium salts are [[nephrotoxic]], and synthetic chemically reactive germanium compounds with [[halogen]]s and [[hydrogen]] are irritants and toxins.
 == History ==
@@ Line 15: / Line 15: @@
 [[File:Winkler Clemens.jpg|thumb|[[Clemens Winkler]]|alt=Photo of a bust of a middle-aged man in a suit with a white short beard and gray moustache.]] THESE PHOTOS are hard to arrange due to the infobox; they are not essential for Germanium-->
 [[File:Mendeleev 1869 prediction of germanium (detail).svg|upright|left|thumb |Prediction of germanium, "?=70" (periodic table 1869)]]
-In his report on ''The Periodic Law of the Chemical Elements'' in 1869, the Russian chemist [[Dmitri Mendeleev]] predicted the existence of several unknown chemical elements, including one that would fill a gap in the [[group 14 element|carbon family]], located between [[silicon]] and [[tin]].<ref>{{cite journal |first=Masanori |last=Kaji |title=D. I. Mendeleev's concept of chemical elements and ''The Principles of Chemistry'' |journal=Bulletin for the History of Chemistry |volume=27 |issue=1 |pages=4–16 |year=2002 |doi=10.70359/bhc2002v027p004 |url=http://www.scs.uiuc.edu/~mainzv/HIST/awards/OPA%20Papers/2005-Kaji.pdf |access-date=2008-08-20 |archive-url=https://web.archive.org/web/20081217080509/http://www.scs.uiuc.edu/~mainzv/HIST/awards/OPA%20Papers/2005-Kaji.pdf |archive-date=2008-12-17 |url-status=dead}}</ref> Because of its position in his periodic table, Mendeleev called it ''ekasilicon (Es)'', and he estimated its [[atomic weight]] to be 70 (later 72).<!-- Mendeleev studied several minerals in an unsuccessful search for this new element.<ref name="vdk">{{cite web |title=Elementymology & Elements Multidict: Germanium |first=Peter |last=van der Krogt |url=http://elements.vanderkrogt.net/element.php?sym=Ge |access-date=2008-08-20}}</ref> -->
+In his report on ''The Periodic Law of the Chemical Elements'' in 1869, the Russian chemist [[Dmitri Mendeleev]] predicted the existence of several unknown chemical elements, including one that would fill a gap in the [[group 14 element|carbon family]], located between [[silicon]] and [[tin]].<ref>{{cite journal |first=Masanori |last=Kaji |title=D. I. Mendeleev's concept of chemical elements and ''The Principles of Chemistry'' |journal=Bulletin for the History of Chemistry |volume=27 |issue=1 |pages=4–16 |year=2002 |doi=10.70359/bhc2002v027p004 |url=http://www.scs.uiuc.edu/~mainzv/HIST/awards/OPA%20Papers/2005-Kaji.pdf |access-date=2008-08-20 |archive-url=https://web.archive.org/web/20081217080509/http://www.scs.uiuc.edu/~mainzv/HIST/awards/OPA%20Papers/2005-Kaji.pdf |archive-date=2008-12-17 }}</ref> Because of its position in his periodic table, Mendeleev called it ''ekasilicon (Es)'', and he estimated its [[atomic weight]] to be 70 (later 72).<!-- Mendeleev studied several minerals in an unsuccessful search for this new element.<ref name="vdk">{{cite web |title=Elementymology & Elements Multidict: Germanium |first=Peter |last=van der Krogt |url=http://elements.vanderkrogt.net/element.php?sym=Ge |access-date=2008-08-20}}</ref> -->
-<!-- [[File:Winkler preparate 1886 1904.png|thumb|left|Samples of germanium compounds prepared by Freiberg University's [[Clemens Winkler]], discoverer of the element]] -->In mid-1885, at a mine near [[Freiberg, Saxony]], a new [[mineral]] was discovered and named ''[[argyrodite]]'' because of its high [[silver]] content.{{NoteTag|From Greek, ''argyrodite'' means ''silver-containing''.<ref>{{cite report |url=http://www.handbookofmineralogy.org/pdfs/argyrodite.pdf |publisher=Mineral Data Publishing |title=Argyrodite – {{chem|Ag|8|GeS|6}} |access-date=2008-09-01 |date= |archive-date=2016-03-03 |archive-url=https://web.archive.org/web/20160303221645/http://www.handbookofmineralogy.org/pdfs/argyrodite.pdf |url-status=live}}</ref>}} The chemist [[Clemens Winkler]] analyzed this new mineral, which proved to be a combination of silver, sulfur, and a new element. Winkler was able to isolate the new element in 1886 and found it similar to [[antimony]]. He initially considered the new element to be eka-antimony, but was soon convinced that it was instead eka-silicon.<ref name="Winkle2" /><ref name="isolation">{{cite journal |journal=Berichte der Deutschen Chemischen Gesellschaft |volume=19 |issue=1 |pages=210–211 |title=Germanium, Ge, a New Nonmetal Element |language=de |first=Clemens |last=Winkler |author-link=Clemens Winkler |year=1887 |doi=10.1002/cber.18860190156 |url=http://gallica.bnf.fr/ark%3A/12148/bpt6k90705g/f212.chemindefer |url-status=dead |archive-url=https://web.archive.org/web/20081207033757/http://dbhs.wvusd.k12.ca.us/webdocs/Chem-History/Disc-of-Germanium.html |archive-date=December 7, 2008}}</ref> Before Winkler published his results on the new element, he decided that he would name his element ''neptunium'', since the recent discovery of planet [[Neptune]] in 1846 had similarly been preceded by mathematical predictions of its existence.{{NoteTag|Just as the existence of the new element had been predicted, the existence of the planet [[Neptune]] had been predicted in about 1843 by the two mathematicians [[John Couch Adams]] and [[Urbain Le Verrier]], using the calculation methods of [[celestial mechanics]]. They did this in attempts to explain the fact that the planet [[Uranus]], upon very close observation, appeared to be being pulled slightly out of position in the sky.<ref>{{cite journal |first=J. C. |last=Adams |bibcode=1846MNRAS...7..149A |title=Explanation of the observed irregularities in the motion of Uranus, on the hypothesis of disturbance by a more distant planet |journal=[[Monthly Notices of the Royal Astronomical Society]] |volume=7 |issue=9 |pages=149–152 |date=November 13, 1846 |doi=10.1093/mnras/7.9.149 |url=https://zenodo.org/record/1431905 |access-date=August 25, 2019 |archive-date=May 2, 2019 |archive-url=https://web.archive.org/web/20190502014753/https://zenodo.org/record/1431905/files/article.pdf |url-status=live |doi-access=free}}</ref> [[James Challis]] started searching for it in July 1846, and he sighted this planet on September 23, 1846.<ref>{{cite journal |first=Rev. J. |last=Challis |bibcode=1846MNRAS...7..145C |title=Account of observations at the Cambridge observatory for detecting the planet exterior to Uranus |journal=Monthly Notices of the Royal Astronomical Society |volume=7 |issue=9 |pages=145–149 |date=November 13, 1846 |doi=10.1093/mnras/7.9.145 |url=https://zenodo.org/record/1431903 |access-date=August 25, 2019 |archive-date=May 4, 2019 |archive-url=https://web.archive.org/web/20190504065619/https://zenodo.org/record/1431903/files/article.pdf |url-status=live |doi-access=free}}</ref>}} However, the name "neptunium" had already been given to another proposed chemical element (though not the element that today bears the name [[neptunium]], which was discovered in 1940).{{NoteTag|R. Hermann published claims in 1877 of his discovery of a new element beneath [[tantalum]] in the periodic table, which he named ''neptunium'', after the Greek god of the oceans and seas.<ref>{{cite journal |title=Scientific Miscellany |journal=The Galaxy |volume=24 |issue=1 |date=July 1877 |page=131 |isbn=978-0-665-50166-1 |first=Robert |last=Sears |oclc=16890343}}</ref><ref>{{cite journal |title=Editor's Scientific Record |journal=Harper's New Monthly Magazine |volume=55 |issue=325 |date=June 1877 |pages=152–153 |url=http://cdl.library.cornell.edu/cgi-bin/moa/moa-cgi?notisid=ABK4014-0055-21 |access-date=2008-09-22 |archive-date=2012-05-26 |archive-url=https://archive.today/20120526215615/http://cdl.library.cornell.edu/cgi-bin/moa/moa-cgi?notisid=ABK4014-0055-21 |url-status=live}}</ref> However this [[metal]] was later recognized to be an [[alloy]] of the elements [[niobium]] and tantalum.<ref>{{cite web |title=Elementymology & Elements Multidict: Niobium |first=Peter |last=van der Krogt |url=http://elements.vanderkrogt.net/element.php?sym=Nb |access-date=2008-08-20 |archive-date=2010-01-23 |archive-url=https://web.archive.org/web/20100123002753/http://elements.vanderkrogt.net/element.php?sym=Nb |url-status=live}}</ref> The name "[[neptunium]]" was later given to the synthetic element one step past [[uranium]] in the Periodic Table, which was discovered by [[nuclear physics]] researchers in 1940.<ref>{{cite book |title=Nobel Lectures, Chemistry 1942–1962 |publisher=Elsevier |date=1964 |chapter=The Nobel Prize in Chemistry 1951: presentation speech |first=A. |last=Westgren |chapter-url=http://nobelprize.org/nobel_prizes/chemistry/laureates/1951/press.html |access-date=2008-09-18 |archive-date=2008-12-10 |archive-url=https://web.archive.org/web/20081210174205/http://nobelprize.org/nobel_prizes/chemistry/laureates/1951/press.html |url-status=live}}</ref>}} So instead, Winkler named the new element ''germanium'' (from the [[Latin]] word, ''[[Germania]]'', for Germany) in honor of his homeland.<ref name="isolation" /> Argyrodite proved empirically to be Ag<sub>8</sub>GeS<sub>6</sub>.
+<!-- [[File:Winkler preparate 1886 1904.png|thumb|left|Samples of germanium compounds prepared by Freiberg University's [[Clemens Winkler]], discoverer of the element]] -->In mid-1885, at a mine near [[Freiberg, Saxony]], a new [[mineral]] was discovered and named ''[[argyrodite]]'' because of its high [[silver]] content.{{NoteTag|From Greek, ''argyrodite'' means ''silver-containing''.<ref>{{cite report |url=http://www.handbookofmineralogy.org/pdfs/argyrodite.pdf |publisher=Mineral Data Publishing |title=Argyrodite – {{chem|Ag|8|GeS|6}} |access-date=2008-09-01 |date= |archive-date=2016-03-03 |archive-url=https://web.archive.org/web/20160303221645/http://www.handbookofmineralogy.org/pdfs/argyrodite.pdf |url-status=live}}</ref>}} The chemist [[Clemens Winkler]] analyzed this new mineral, which proved to be a combination of silver, sulfur, and a new element. Winkler was able to isolate the new element in 1886 and found it similar to [[antimony]]. He initially considered the new element to be eka-antimony, but was soon convinced that it was instead eka-silicon.<ref name="Winkle2" /><ref name="isolation">{{cite journal |journal=Berichte der Deutschen Chemischen Gesellschaft |volume=19 |issue=1 |pages=210–211 |title=Germanium, Ge, a New Nonmetal Element |language=de |first=Clemens |last=Winkler |author-link=Clemens Winkler |year=1887 |doi=10.1002/cber.18860190156 |url=http://gallica.bnf.fr/ark%3A/12148/bpt6k90705g/f212.chemindefer |archive-url=https://web.archive.org/web/20081207033757/http://dbhs.wvusd.k12.ca.us/webdocs/Chem-History/Disc-of-Germanium.html |archive-date=December 7, 2008}}</ref> Before Winkler published his results on the new element, he decided that he would name his element ''neptunium'', since the recent discovery of planet [[Neptune]] in 1846 had similarly been preceded by mathematical predictions of its existence.{{NoteTag|Just as the existence of the new element had been predicted, the existence of the planet [[Neptune]] had been predicted in about 1843 by the two mathematicians [[John Couch Adams]] and [[Urbain Le Verrier]], using the calculation methods of [[celestial mechanics]]. They did this in attempts to explain the fact that the planet [[Uranus]], upon very close observation, appeared to be being pulled slightly out of position in the sky.<ref>{{cite journal |first=J. C. |last=Adams |bibcode=1846MNRAS...7..149A |title=Explanation of the observed irregularities in the motion of Uranus, on the hypothesis of disturbance by a more distant planet |journal=[[Monthly Notices of the Royal Astronomical Society]] |volume=7 |issue=9 |pages=149–152 |date=November 13, 1846 |doi=10.1093/mnras/7.9.149 |url=https://zenodo.org/record/1431905 |access-date=August 25, 2019 |archive-date=May 2, 2019 |archive-url=https://web.archive.org/web/20190502014753/https://zenodo.org/record/1431905/files/article.pdf |url-status=live |doi-access=free}}</ref> [[James Challis]] started searching for it in July 1846, and he sighted this planet on September 23, 1846.<ref>{{cite journal |first=Rev. J. |last=Challis |bibcode=1846MNRAS...7..145C |title=Account of observations at the Cambridge observatory for detecting the planet exterior to Uranus |journal=Monthly Notices of the Royal Astronomical Society |volume=7 |issue=9 |pages=145–149 |date=November 13, 1846 |doi=10.1093/mnras/7.9.145 |url=https://zenodo.org/record/1431903 |access-date=August 25, 2019 |archive-date=May 4, 2019 |archive-url=https://web.archive.org/web/20190504065619/https://zenodo.org/record/1431903/files/article.pdf |url-status=live |doi-access=free}}</ref>}} However, the name "neptunium" had already been given to another proposed chemical element (though not the element that today bears the name [[neptunium]], which was discovered in 1940).{{NoteTag|R. Hermann published claims in 1877 of his discovery of a new element beneath [[tantalum]] in the periodic table, which he named ''neptunium'', after the Greek god of the oceans and seas.<ref>{{cite journal |title=Scientific Miscellany |url=https://archive.org/details/sim_galaxy_1877-07_24_1/page/130 |journal=The Galaxy |volume=24 |issue=1 |date=July 1877 |page=131 |isbn=978-0-665-50166-1 |first=Robert |last=Sears |oclc=16890343}}</ref><ref>{{cite journal |title=Editor's Scientific Record |journal=Harper's New Monthly Magazine |volume=55 |issue=325 |date=June 1877 |pages=152–153 |url=https://cdl.library.cornell.edu/cgi-bin/moa/moa-cgi?notisid=ABK4014-0055-21 |access-date=2008-09-22 |archive-date=2012-05-26 |archive-url=https://archive.today/20120526215615/http://cdl.library.cornell.edu/cgi-bin/moa/moa-cgi?notisid=ABK4014-0055-21 |url-status=live}}</ref> However this [[metal]] was later recognized to be an [[alloy]] of the elements [[niobium]] and tantalum.<ref>{{cite web |title=Elementymology & Elements Multidict: Niobium |first=Peter |last=van der Krogt |url=http://elements.vanderkrogt.net/element.php?sym=Nb |access-date=2008-08-20 |archive-date=2010-01-23 |archive-url=https://web.archive.org/web/20100123002753/http://elements.vanderkrogt.net/element.php?sym=Nb |url-status=live}}</ref> The name "[[neptunium]]" was later given to the synthetic element one step past [[uranium]] in the Periodic Table, which was discovered by [[nuclear physics]] researchers in 1940.<ref>{{cite book |title=Nobel Lectures, Chemistry 1942–1962 |publisher=Elsevier |date=1964 |chapter=The Nobel Prize in Chemistry 1951: presentation speech |first=A. |last=Westgren |chapter-url=http://nobelprize.org/nobel_prizes/chemistry/laureates/1951/press.html |access-date=2008-09-18 |archive-date=2008-12-10 |archive-url=https://web.archive.org/web/20081210174205/http://nobelprize.org/nobel_prizes/chemistry/laureates/1951/press.html |url-status=live}}</ref>}} So instead, Winkler named the new element ''germanium'' (from the [[Latin]] word, ''[[Germania]]'', for Germany) in honor of his homeland.<ref name="isolation" /> Argyrodite proved empirically to be Ag<sub>8</sub>GeS<sub>6</sub>.
-Because this new element showed some similarities with the elements [[arsenic]] and antimony, its proper place in the periodic table was under consideration, but its similarities with Dmitri Mendeleev's predicted element "ekasilicon" confirmed that place on the periodic table.<ref name="isolation" /><ref>{{cite journal |journal=The Manufacturer and Builder |url=http://cdl.library.cornell.edu/cgi-bin/moa/pageviewer?frames=1&coll=moa&view=50&root=%2Fmoa%2Fmanu%2Fmanu0018%2F&tif=00187.TIF |year=1887 |title=Germanium, a New Non-Metallic Element |page=181 |access-date=2008-08-20 |archive-date=2008-12-19 |archive-url=https://web.archive.org/web/20081219162737/http://cdl.library.cornell.edu/cgi-bin/moa/pageviewer?frames=1&coll=moa&view=50&root=%2Fmoa%2Fmanu%2Fmanu0018%2F&tif=00187.TIF |url-status=live}}</ref> With further material from 500&nbsp;kg of ore from the mines in Saxony, Winkler confirmed the chemical properties of the new element in 1887.<ref name="Winkle2">{{cite journal |first=Clemens |last=Winkler |author-link=Clemens Winkler |journal=J. Prak. Chemie |volume=36 |issue=1 |date=1887 |pages=177–209 |title=Mittheilungen über des Germanium. Zweite Abhandlung |doi=10.1002/prac.18870360119 |url=http://gallica.bnf.fr/ark:/12148/bpt6k90799n/f183.table |access-date=2008-08-20 |language=de |archive-date=2012-11-03 |archive-url=https://web.archive.org/web/20121103012004/http://gallica.bnf.fr/ark:/12148/bpt6k90799n/f183.table |url-status=live}}</ref><ref name="isolation" /><ref>{{cite journal |first=O. |last=Brunck |title=Obituary: Clemens Winkler |journal=Berichte der Deutschen Chemischen Gesellschaft |volume=39 |issue=4 |year=1886 |pages=4491–4548 |doi=10.1002/cber.190603904164 |url=https://zenodo.org/record/1426200 |language=de |access-date=2020-06-07 |archive-date=2020-08-01 |archive-url=https://web.archive.org/web/20200801004057/https://zenodo.org/record/1426200 |url-status=live}}</ref> He also determined an atomic weight of 72.32 by analyzing pure [[germanium tetrachloride]] ({{chem|GeCl|4}}), while [[Lecoq de Boisbaudran]] deduced 72.3 by a comparison of the lines in the spark [[spectrum]] of the element.<ref>{{cite journal |title=Sur le poids atomique du germanium |first=M. Lecoq |last=de Boisbaudran |journal=Comptes Rendus |year=1886 |volume=103 |page=452 |url=http://gallica.bnf.fr/ark:/12148/bpt6k3059r/f454.table |access-date=2008-08-20 |language=fr |archive-date=2013-06-20 |archive-url=https://web.archive.org/web/20130620032945/http://gallica.bnf.fr/ark:/12148/bpt6k3059r/f454.table |url-status=live}}</ref>
+Because this new element showed some similarities with the elements [[arsenic]] and antimony, its proper place in the periodic table was under consideration, but its similarities with Dmitri Mendeleev's predicted element "ekasilicon" confirmed that place on the periodic table.<ref name="isolation" /><ref>{{cite journal |journal=The Manufacturer and Builder |url=https://cdl.library.cornell.edu/cgi-bin/moa/pageviewer?frames=1&coll=moa&view=50&root=%2Fmoa%2Fmanu%2Fmanu0018%2F&tif=00187.TIF |year=1887 |title=Germanium, a New Non-Metallic Element |page=181 |access-date=2008-08-20 |archive-date=2008-12-19 |archive-url=https://web.archive.org/web/20081219162737/http://cdl.library.cornell.edu/cgi-bin/moa/pageviewer?frames=1&coll=moa&view=50&root=%2Fmoa%2Fmanu%2Fmanu0018%2F&tif=00187.TIF |url-status=live}}</ref> With further material from 500&nbsp;kg of ore from the mines in Saxony, Winkler confirmed the chemical properties of the new element in 1887.<ref name="Winkle2">{{cite journal |first=Clemens |last=Winkler |author-link=Clemens Winkler |journal=J. Prak. Chemie |volume=36 |issue=1 |date=1887 |pages=177–209 |title=Mittheilungen über des Germanium. Zweite Abhandlung |doi=10.1002/prac.18870360119 |url=http://gallica.bnf.fr/ark:/12148/bpt6k90799n/f183.table |access-date=2008-08-20 |language=de |archive-date=2012-11-03 |archive-url=https://web.archive.org/web/20121103012004/http://gallica.bnf.fr/ark:/12148/bpt6k90799n/f183.table |url-status=live}}</ref><ref name="isolation" /><ref>{{cite journal |first=O. |last=Brunck |title=Obituary: Clemens Winkler |journal=Berichte der Deutschen Chemischen Gesellschaft |volume=39 |issue=4 |year=1886 |pages=4491–4548 |doi=10.1002/cber.190603904164 |url=https://zenodo.org/record/1426200 |language=de |access-date=2020-06-07 |archive-date=2020-08-01 |archive-url=https://web.archive.org/web/20200801004057/https://zenodo.org/record/1426200 |url-status=live}}</ref> He also determined an atomic weight of 72.32 by analyzing pure [[germanium tetrachloride]] ({{chem|GeCl|4}}), while [[Lecoq de Boisbaudran]] deduced 72.3 by a comparison of the lines in the spark [[spectrum]] of the element.<ref>{{cite journal |title=Sur le poids atomique du germanium |first=M. Lecoq |last=de Boisbaudran |journal=Comptes Rendus |year=1886 |volume=103 |page=452 |url=http://gallica.bnf.fr/ark:/12148/bpt6k3059r/f454.table |access-date=2008-08-20 |language=fr |archive-date=2013-06-20 |archive-url=https://web.archive.org/web/20130620032945/http://gallica.bnf.fr/ark:/12148/bpt6k3059r/f454.table |url-status=live}}</ref>
 Winkler was able to prepare several new compounds of germanium, including [[Germanium fluoride|fluorides]], [[Germanium chloride|chlorides]], [[Germanium sulfide (disambiguation)|sulfides]]<!--intentional link to DAB page-->, [[Germanium dioxide|dioxide]], and [[tetraethylgermane]] (Ge(C<sub>2</sub>H<sub>5</sub>)<sub>4</sub>), the first organogermane.<ref name="Winkle2" /> The physical data from those compounds—which corresponded well with Mendeleev's predictions—made the discovery an important confirmation of Mendeleev's idea of element [[Periodic table|periodicity]]. Here is a comparison between the prediction and Winkler's data:<ref name="Winkle2" />
@@ Line 46: / Line 46: @@
 |}</div>
-Until the late 1930s, germanium was thought to be a poorly conducting [[metal]].<ref name="DOE">{{cite journal |title=Germanium: From Its Discovery to SiGe Devices |author=Haller, E. E. |website=Department of Materials Science and Engineering, University of California, Berkeley, and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley |url=http://www.osti.gov/bridge/servlets/purl/922705-bthJo6/922705.PDF |access-date=2008-08-22 |date=2006-06-14 |archive-date=2019-07-10 |archive-url=https://web.archive.org/web/20190710154435/http://www.osti.gov/bridge/servlets/purl/922705-bthJo6/922705.PDF |url-status=live}}</ref> Germanium did not become economically significant until after 1945 when its properties as an [[electronics|electronic]] semiconductor were recognized. During [[World War II]], small amounts of germanium were used in some special [[electronics|electronic devices]], mostly [[diode]]s.<ref>{{cite news |author=W. K. |url=http://select.nytimes.com/gst/abstract.html?res=F30715FE3F5B157A93C2A8178ED85F478585F9 |newspaper=The New York Times |title=Germanium for Electronic Devices |access-date=2008-08-22 |date=1953-05-10 |archive-date=2013-06-13 |archive-url=https://web.archive.org/web/20130613202934/http://select.nytimes.com/gst/abstract.html?res=F30715FE3F5B157A93C2A8178ED85F478585F9 |url-status=live}}</ref><ref>{{cite web |url=http://www.computerhistory.org/semiconductor/timeline/1941-semiconductor.html |title=1941 – Semiconductor diode rectifiers serve in WW II |publisher=Computer History Museum |access-date=2008-08-22 |archive-date=2008-09-24 |archive-url=https://web.archive.org/web/20080924135754/http://www.computerhistory.org/semiconductor/timeline/1941-semiconductor.html |url-status=live}}</ref> The first major use was the point-contact [[Schottky diode]]s for [[radar]] pulse detection during the War.<ref name="DOE" /> The first [[silicon–germanium]] alloys were obtained in 1955.<ref>{{cite web |url=http://www.sp.phy.cam.ac.uk/~SiGe/Silicon%20Germanium%20(SiGe)%20History.html |title=SiGe History |publisher=University of Cambridge |access-date=2008-08-22 |url-status=dead |archive-url=https://web.archive.org/web/20080805204801/http://www.sp.phy.cam.ac.uk/~SiGe/Silicon%20Germanium%20%28SiGe%29%20History.html |archive-date=2008-08-05}}</ref> Before 1945, only a few hundred kilograms of germanium were produced in smelters each year, but by the end of the 1950s, the annual worldwide production had reached {{convert|40|MT|ST|lk=on|abbr=off}}.<ref name="acs">{{cite news |url=http://pubs.acs.org/cen/80th/print/germanium.html |year=2003 |title=Germanium |first=Bethany |last=Halford |work=Chemical & Engineering News |publisher=American Chemical Society |access-date=2008-08-22 |archive-date=2008-05-13 |archive-url=https://web.archive.org/web/20080513180858/http://pubs.acs.org/cen/80th/print/germanium.html |url-status=live}}</ref>
+Until the late 1930s, germanium was thought to be a poorly conducting [[metal]].<ref name="DOE">{{cite journal |title=Germanium: From Its Discovery to SiGe Devices |author=Haller, E. E. |website=Department of Materials Science and Engineering, University of California, Berkeley, and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley |url=http://www.osti.gov/bridge/servlets/purl/922705-bthJo6/922705.PDF |access-date=2008-08-22 |date=2006-06-14 |archive-date=2019-07-10 |archive-url=https://web.archive.org/web/20190710154435/http://www.osti.gov/bridge/servlets/purl/922705-bthJo6/922705.PDF |url-status=live}}</ref> Germanium did not become economically significant until after 1945 when its properties as an [[electronics|electronic]] semiconductor were recognized. During [[World War II]], small amounts of germanium were used in some special [[electronics|electronic devices]], mostly [[diode]]s.<ref>{{cite news |author=W. K. |url=http://select.nytimes.com/gst/abstract.html?res=F30715FE3F5B157A93C2A8178ED85F478585F9 |newspaper=The New York Times |title=Germanium for Electronic Devices |access-date=2008-08-22 |date=1953-05-10 |archive-date=2013-06-13 |archive-url=https://web.archive.org/web/20130613202934/http://select.nytimes.com/gst/abstract.html?res=F30715FE3F5B157A93C2A8178ED85F478585F9 |url-status=live}}</ref><ref>{{cite web |url=http://www.computerhistory.org/semiconductor/timeline/1941-semiconductor.html |title=1941 – Semiconductor diode rectifiers serve in WW II |publisher=Computer History Museum |access-date=2008-08-22 |archive-date=2008-09-24 |archive-url=https://web.archive.org/web/20080924135754/http://www.computerhistory.org/semiconductor/timeline/1941-semiconductor.html |url-status=live}}</ref> The first major use was the point-contact [[Schottky diode]]s for [[radar]] pulse detection during the War.<ref name="DOE" /> The first [[silicon–germanium]] alloys were obtained in 1955.<ref>{{cite web |url=http://www.sp.phy.cam.ac.uk/~SiGe/Silicon%20Germanium%20(SiGe)%20History.html |title=SiGe History |publisher=University of Cambridge |access-date=2008-08-22 |archive-url=https://web.archive.org/web/20080805204801/http://www.sp.phy.cam.ac.uk/~SiGe/Silicon%20Germanium%20%28SiGe%29%20History.html |archive-date=2008-08-05}}</ref> Before 1945, only a few hundred kilograms of germanium were produced in smelters each year, but by the end of the 1950s, the annual worldwide production had reached {{convert|40|MT|ST|lk=on|abbr=off}}.<ref name="acs">{{cite news |url=http://pubs.acs.org/cen/80th/print/germanium.html |year=2003 |title=Germanium |first=Bethany |last=Halford |work=Chemical & Engineering News |publisher=American Chemical Society |access-date=2008-08-22 |archive-date=2008-05-13 |archive-url=https://web.archive.org/web/20080513180858/http://pubs.acs.org/cen/80th/print/germanium.html |url-status=live}}</ref>
-The development of the germanium [[transistor]] in 1948<ref>{{cite journal |journal=Physical Review |volume=74 |issue=2 |pages=230–231 |title=The Transistor, A Semi-Conductor Triode |first=J. |last=Bardeen |author2=Brattain, W. H. |year=1948 |doi=10.1103/PhysRev.74.230 |bibcode=1948PhRv...74..230B |doi-access=free}}</ref> opened the door to countless applications of [[solid state (electronics)|solid state electronics]].<ref>{{cite web |title=Electronics History 4 – Transistors |url=http://www.greatachievements.org/?id=3967 |publisher=National Academy of Engineering |access-date=2008-08-22 |archive-date=2007-10-20 |archive-url=https://web.archive.org/web/20071020030644/http://www.greatachievements.org/?id=3967 |url-status=live}}</ref> From 1950 through the early 1970s, this area provided an increasing market for germanium, but then high-purity silicon began replacing germanium in transistors, diodes, and [[rectifier]]s.<ref name="usgs">{{cite journal |title=Germanium – Statistics and Information |author=U.S. Geological Survey |year=2008 |journal=U.S. Geological Survey, Mineral Commodity Summaries |url=http://minerals.usgs.gov/minerals/pubs/commodity/germanium/ |quote=Select 2008 |access-date=2008-08-28 |archive-date=2008-09-16 |archive-url=https://web.archive.org/web/20080916115005/http://minerals.usgs.gov/minerals/pubs/commodity/germanium/ |url-status=live}}</ref> For example, the company that became [[Fairchild Semiconductor]] was founded in 1957 with the express purpose of producing silicon transistors. Silicon has superior electrical properties, but it requires much greater purity that could not be commercially achieved in the early years of [[solid-state electronics|semiconductor electronics]].<ref>{{cite journal |journal=IEEE Transactions on Electron Devices |volume=ED-23 |issue=7 |date=July 1976 |title=Single Crystals of Germanium and Silicon-Basic to the Transistor and Integrated Circuit |first=Gordon K. |last=Teal |pages=621–639 |doi=10.1109/T-ED.1976.18464 |bibcode=1976ITED...23..621T |s2cid=11910543}}</ref>
+The development of the germanium [[transistor]] in 1948<ref>{{cite journal |journal=Physical Review |volume=74 |issue=2 |pages=230–231 |title=The Transistor, A Semi-Conductor Triode |first=J. |last=Bardeen |author2=Brattain, W. H. |year=1948 |doi=10.1103/PhysRev.74.230 |bibcode=1948PhRv...74..230B |doi-access=free}}</ref> opened the door to countless applications of [[solid state (electronics)|solid state electronics]].<ref>{{cite web |title=Electronics History 4 – Transistors |url=http://www.greatachievements.org/?id=3967 |publisher=National Academy of Engineering |access-date=2008-08-22 |archive-date=2007-10-20 |archive-url=https://web.archive.org/web/20071020030644/http://www.greatachievements.org/?id=3967 |url-status=live}}</ref> From 1950 through the early 1970s, this area provided an increasing market for germanium, but then high-purity silicon began replacing germanium in transistors, diodes, and [[rectifier]]s.<ref name="usgs">{{cite journal |title=Germanium – Statistics and Information |author=U.S. Geological Survey |year=2008 |journal=U.S. Geological Survey, Mineral Commodity Summaries |url=https://minerals.usgs.gov/minerals/pubs/commodity/germanium/ |quote=Select 2008 |access-date=2008-08-28 |archive-date=2008-09-16 |archive-url=https://web.archive.org/web/20080916115005/http://minerals.usgs.gov/minerals/pubs/commodity/germanium/ |url-status=live}}</ref> For example, the company that became [[Fairchild Semiconductor]] was founded in 1957 with the express purpose of producing silicon transistors. Silicon has superior electrical properties, but it requires much greater purity that could not be commercially achieved in the early years of [[solid-state electronics|semiconductor electronics]].<ref>{{cite journal |journal=IEEE Transactions on Electron Devices |volume=ED-23 |issue=7 |date=July 1976 |title=Single Crystals of Germanium and Silicon-Basic to the Transistor and Integrated Circuit |first=Gordon K. |last=Teal |pages=621–639 |doi=10.1109/T-ED.1976.18464 |bibcode=1976ITED...23..621T |s2cid=11910543}}</ref>
 Meanwhile, the demand for germanium for [[fiber optics|fiber optic]] communication networks, infrared [[night vision]] systems, and [[polymerization]] [[catalysts]] increased dramatically.<ref name="acs" /> These end uses represented 85% of worldwide germanium consumption in 2000.<ref name="usgs" /> The US government even designated germanium as a strategic and critical material, calling for a 146&nbsp;[[Short ton|ton]] (132&nbsp;[[tonne]]) supply in the national defense stockpile in 1987.<ref name="acs" />
@@ Line 56: / Line 56: @@
 == Characteristics ==
-Under [[standard conditions]], germanium is a brittle, silvery-white,<ref name="nbb" /> [[semiconductor]]. This form constitutes an [[allotrope]] known as ''α-germanium'', which has a metallic luster and a [[diamond cubic|diamond cubic crystal structure]], the same structure as [[silicon]] and [[diamond]].<ref name="usgs" /> In this form, germanium has a [[threshold displacement energy]] of <math>19.7^{+0.6}_{-0.5}~\text{eV}</math>.<ref>{{Cite journal |last1=Agnese |first1=R. |last2=Aralis |first2=T. |last3=Aramaki |first3=T. |last4=Arnquist |first4=I. J. |last5=Azadbakht |first5=E. |last6=Baker |first6=W. |last7=Banik |first7=S. |last8=Barker |first8=D. |last9=Bauer |first9=D. A. |date=2018-08-27 |title=Energy loss due to defect formation from 206Pb recoils in SuperCDMS germanium detectors |journal=Applied Physics Letters |volume=113 |issue=9 |pages=092101 |doi=10.1063/1.5041457 |issn=0003-6951 |arxiv=1805.09942 |bibcode=2018ApPhL.113i2101A |s2cid=118627298}}</ref> At pressures above 120&nbsp;[[bar (unit)|kbar]], germanium becomes the metallic allotrope ''β-germanium'' with the same structure as β-[[tin]].<ref name="HollemanAF" /> Like silicon, [[gallium]], [[bismuth]], [[antimony]], and [[water]], germanium is one of the few substances that expands as it solidifies (i.e. [[freezing|freezes]]) from the molten state.<ref name="HollemanAF" />
+Under [[standard conditions]], germanium is a brittle, silvery-white,<ref name="nbb" /> [[semiconductor]]. This form constitutes an [[allotrope]] known as ''α-germanium'', which has a metallic luster and a [[diamond cubic|diamond cubic crystal structure]], the same structure as [[silicon]] and [[diamond]].<ref name="usgs" /> In this form, germanium has a [[threshold displacement energy]] of <math>19.7^{+0.6}_{-0.5}~\text{eV}</math>.<ref>{{Cite journal |last1=Agnese |first1=R. |last2=Aralis |first2=T. |last3=Aramaki |first3=T. |last4=Arnquist |first4=I. J. |last5=Azadbakht |first5=E. |last6=Baker |first6=W. |last7=Banik |first7=S. |last8=Barker |first8=D. |last9=Bauer |first9=D. A. |date=2018-08-27 |title=Energy loss due to defect formation from 206Pb recoils in SuperCDMS germanium detectors |journal=Applied Physics Letters |volume=113 |issue=9 |page=092101 |doi=10.1063/1.5041457 |issn=0003-6951 |arxiv=1805.09942 |bibcode=2018ApPhL.113i2101A |s2cid=118627298}}</ref> At pressures above 120&nbsp;[[bar (unit)|kbar]], germanium becomes the metallic allotrope ''β-germanium'' with the same structure as β-[[tin]].<ref name="HollemanAF" /> Like silicon, [[gallium]], [[bismuth]], [[antimony]], and [[water]], germanium is one of the few substances that expands as it solidifies (i.e. [[freezing|freezes]]) from the molten state.<ref name="HollemanAF" />
 Germanium is a semiconductor having an [[Direct and indirect band gaps|indirect bandgap]], as is crystalline silicon. [[Zone refining]] techniques have led to the production of crystalline germanium for semiconductors that has an impurity of only one part in 10<sup>10</sup>,<ref name="lanl">{{cite web |publisher=Los Alamos National Laboratory |title=Germanium |url=http://periodic.lanl.gov/32.shtml |access-date=2008-08-28 |archive-date=2011-06-22 |archive-url=https://web.archive.org/web/20110622065850/http://periodic.lanl.gov/32.shtml |url-status=live}}</ref>
@@ Line 89: / Line 89: @@
 === Isotopes ===
 {{main|Isotopes of germanium}}
-Germanium occurs in five natural [[isotope]]s: {{SimpleNuclide|Germanium|70}}, {{SimpleNuclide|Germanium|72}}, {{SimpleNuclide|Germanium|73}}, {{SimpleNuclide|Germanium|74}}, and {{SimpleNuclide|Germanium|76}}. Of these, {{SimpleNuclide|Germanium|76}} is very slightly radioactive, decaying by [[double beta decay]] with a [[half-life]] of {{val|1.78|e=21|u=years}}. {{SimpleNuclide|Germanium|74}} is the most common isotope, having a [[natural abundance]] of approximately 36%. {{SimpleNuclide|Germanium|76}} is the least common with a natural abundance of approximately 7%.<ref name="nubase">{{NUBASE 2003}}</ref> When bombarded with alpha particles, the isotope {{SimpleNuclide|Germanium|72}} will generate stable {{SimpleNuclide|Selenium|77|link=yes}}, releasing high energy electrons in the process.<ref name="72Ge" /> Because of this, it is used in combination with [[radon]] for [[Atomic battery|nuclear batteries]].<ref name="72Ge">Perreault, Bruce A. [https://patents.google.com/patent/US7800286 "Alpha Fusion Electrical Energy Valve"], US Patent 7800286, issued September 21, 2010. {{webarchive |url=https://web.archive.org/web/20071012103442/http://www.nuenergy.org/disclosures/AlphaFusionPatent_05-04-2007.pdf |archive-url=https://web.archive.org/web/20071012103442/http://www.nuenergy.org/disclosures/AlphaFusionPatent_05-04-2007.pdf |archive-date=2007-10-12 |url-status=live |date=October 12, 2007 |title=PDF copy }}</ref>
+Germanium occurs in five natural [[isotope]]s: {{SimpleNuclide|Germanium|70}}, {{SimpleNuclide|Germanium|72}}, {{SimpleNuclide|Germanium|73}}, {{SimpleNuclide|Germanium|74}}, and {{SimpleNuclide|Germanium|76}}. Of these, {{SimpleNuclide|Germanium|76}} is very slightly radioactive, undergoing [[double beta decay]] with a [[half-life]] of {{val|2.02|e=21|u=years}}.<ref name="Ge76" /> {{SimpleNuclide|Germanium|74}} is the most common isotope, having a [[natural abundance]] of 36.52% and {{SimpleNuclide|Germanium|76}} is the least common with a natural abundance of 7.75%.<ref name="nubase">{{NUBASE2020}}</ref>
-At least 27 [[radioisotope]]s have also been synthesized, ranging in atomic mass from 58 to 89. The most stable of these is {{SimpleNuclide|Germanium|68}}, decaying by [[electron capture]] with a half-life of {{val|270.95|u=days}}ays. The least stable is {{SimpleNuclide|Germanium|60}}, with a half-life of {{val|30|ul=ms}}. While most of germanium's radioisotopes decay by [[beta decay]], {{SimpleNuclide|Germanium|61}} and {{SimpleNuclide|Germanium|64}} decay by [[Positron emission|{{SubatomicParticle|beta+}}]] delayed [[proton emission]].<ref name="nubase" /> {{SimpleNuclide|Germanium|84}} through {{SimpleNuclide|Germanium|87}} isotopes also exhibit minor [[Beta decay|{{SubatomicParticle|beta-}}]] delayed [[neutron emission]] decay paths.<ref name="nubase" />
+Apart from {{SimpleNuclide|Germanium|76}}, at least 27 other [[radioisotope]]s have been synthesized, ranging in atomic mass from 58 to 89. The most stable of these is {{SimpleNuclide|Germanium|68}}, decaying by [[electron capture]] with a half-life of {{val|270.95|u=days}}. This is followed by {{SimpleNuclide|Germanium|71}}, also decaying by electron capture with half-life {{val|11.468|u=days}},<ref name="norman2024" /> and the rest are all less than two days, most under two hours.<ref name="nubase" />
 === Occurrence ===
@@ Line 105: / Line 105: @@
 <div style="float: right; margin: 5px;">
 {|class="wikitable" style="font-size:85%; text-align:right;"
-!Year !! Cost<br />([[United States dollar|$]]/kg)<ref><!--two sources in one here?-->{{Cite book |title=USGS Minerals Information |url=http://minerals.usgs.gov/minerals/pubs/commodity/germanium/index.html#mcs |at=[http://minerals.usgs.gov/minerals/pubs/commodity/germanium/220303.pdf January 2003], [http://minerals.usgs.gov/minerals/pubs/commodity/germanium/germamcs04.pdf January 2004], [http://minerals.usgs.gov/minerals/pubs/commodity/germanium/germamcs05.pdf January 2005], [http://minerals.usgs.gov/minerals/pubs/commodity/germanium/germamcs06.pdf January 2006], [http://minerals.usgs.gov/minerals/pubs/commodity/germanium/germamcs07.pdf January 2007], [http://minerals.usgs.gov/minerals/pubs/commodity/germanium/mcs-2010-germa.pdf January 2010] |isbn=978-0-85934-039-7 |author=R.N. Soar |oclc=16437701 |date=1977 |publisher=Babani Press |access-date=2013-04-22 |archive-date=2013-05-07 |archive-url=https://web.archive.org/web/20130507125723/http://minerals.usgs.gov/minerals/pubs/commodity/germanium/index.html#mcs |url-status=live}}</ref>
+!Year !! Cost<br />([[United States dollar|$]]/kg)<ref><!--two sources in one here?-->{{Cite book |title=USGS Minerals Information |url=https://minerals.usgs.gov/minerals/pubs/commodity/germanium/index.html#mcs |at=[https://minerals.usgs.gov/minerals/pubs/commodity/germanium/220303.pdf January 2003], [https://minerals.usgs.gov/minerals/pubs/commodity/germanium/germamcs04.pdf January 2004], [https://minerals.usgs.gov/minerals/pubs/commodity/germanium/germamcs05.pdf January 2005], [https://minerals.usgs.gov/minerals/pubs/commodity/germanium/germamcs06.pdf January 2006], [https://minerals.usgs.gov/minerals/pubs/commodity/germanium/germamcs07.pdf January 2007], [https://minerals.usgs.gov/minerals/pubs/commodity/germanium/mcs-2010-germa.pdf January 2010] |isbn=978-0-85934-039-7 |author=R.N. Soar |oclc=16437701 |date=1977 |publisher=Babani Press |access-date=2013-04-22 |archive-date=2013-05-07 |archive-url=https://web.archive.org/web/20130507125723/http://minerals.usgs.gov/minerals/pubs/commodity/germanium/index.html#mcs |url-status=live}}</ref>
 |-
 |1999 || 1,400
@@ Line 170: / Line 170: @@
 : GeO<sub>2</sub> + C → Ge + CO<sub>2</sub>
+=== Production by country ===
+World refinery production of germanium (germanium content).
+{| class="wikitable"
+|+ World refinery production / total supply (USGS), with country groups where available
+! Year !! China (t) !! Canada (t) !! Russia (t) !! Other (t) !! U.S. refinery (t) !! World total (t) !! Comment !! Source
+|-
+| 1970 ||   ||   ||   ||   || ~15 || ~85 ||  || <ref name = "Butterman2005">{{cite report |last1=Butterman |first1=W. C. |last2=Jorgenson |first2=John D. |title=Mineral Commodity Profiles: Germanium |series=Open-File Report |number=2004–1218 |publisher=U.S. Geological Survey |location=Reston, Virginia |date=2005 |url=https://pubs.usgs.gov/of/2004/1218/2004-1218.pdf |access-date=2025-09-28 |at=fig. 4}}</ref>
+|-
+| 1980 ||   ||   || 14 ||   || 27 || ~115 || USSR 14 (est.), Japan 13 t, France 10, Austria 5. Significant recovery also believed in Belgium, China, FRG, Italy. || <ref>{{cite report |title=World mineral statistics 1980–84: production: exports: imports |publisher=British Geological Survey |year=1986 |url=https://nora.nerc.ac.uk/id/eprint/535250/1/WMS_1980_1984.pdf |page=286 |access-date=28 September 2025}}</ref><ref name = "Butterman2005"/>
+|-
+| 1990 || 10 || - || 12 ||   || 18 || ~80 || USSR 12 t, Japan 3 t, Austria 5 t || <ref>{{cite report |title=World Mineral Statistics 1990–94: production: exports: imports |publisher=British Geological Survey |year=1995 |url=https://nora.nerc.ac.uk/id/eprint/535237/1/WMS_1990_1994.pdf |page=300 |access-date=28 September 2025}}</ref><ref name = "Butterman2005"/>
+|-
+| 1996 ||   ||   ||   ||   || 18 || 71.5 || World total market supply ≈71.5 t (≈53 t primary refinery + 12 t recycling + 6.5 t stock releases) || <ref>{{cite report |title=Germanium—1996 Minerals Yearbook |publisher=U.S. Geological Survey |url=https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/mineral-pubs/germanium/220496.pdf |access-date=28 September 2025}}</ref>
+|-
+| 1999 ||   ||   ||   ||   || 20 || 91 || World total market supply (58 t primary refinery + 25 t recycling + 8 t stock releases) || <ref>{{cite report |last=Brown Jr. |first=Robert D. |title=Germanium—1999 |work=Minerals Yearbook |publisher=U.S. Geological Survey |url=https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/mineral-pubs/germanium/220499.pdf |access-date=27 September 2025}}</ref>
+|-
+| 2000 ||   ||   ||   ||   || 23 || 105 ||  World total market supply (slightly >70 t primary refinery + 25 t recycling + 9 t stock releases) || <ref>{{cite report |title=Germanium—2000 Minerals Yearbook |publisher=U.S. Geological Survey |url=https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/mineral-pubs/germanium/220400.pdf |access-date=27 September 2025}}</ref>
+|-
+| 2001 ||   ||   ||   ||   || 20 || 110 || World total market supply (~<70 t primary refinery + 30 t recycling + 12 t stock releases) || <ref>{{cite report |title=Germanium—2001 Minerals Yearbook |publisher=U.S. Geological Survey |url=https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/mineral-pubs/germanium/germmyb01.pdf |access-date=27 September 2025}}</ref>
+|-
+| 2002 ||   ||   ||   ||   || 12 || 80 || World total market supply (50 t primary refinery + 30 t recycling) || <ref>{{cite report |title=Germanium—2002 Minerals Yearbook |publisher=U.S. Geological Survey |url=https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/mineral-pubs/germanium/germmyb02.pdf |access-date=27 September 2025}}</ref>
+|-
+| 2003 ||   ||   ||   ||   || 12 || 80 || World total market supply (50 t primary refinery + 30 t recycling) - "Starting in 2001, there had been a growing surplus of germanium owing to a major downturn in the fiber optics market. By yearend 2003, supply and demand were in close balance" || <ref>{{cite report |title=Germanium—2003 Minerals Yearbook |publisher=U.S. Geological Survey |url=https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/mineral-pubs/germanium/germamyb03.pdf |access-date=27 September 2025}}</ref>
+|-
+| 2004 ||   ||   ||   ||   || 4.4 || 87 || World total market supply (50 t primary refinery + 30 t recycling + 7 t stock releases) || <ref name = "Butterman2005"/>
+|-
+| 2005 ||   ||   ||   ||   || 4.5 || 90 || World total market supply (including 31 t recycling) || <ref>{{cite report |title=Germanium—2005 Minerals Yearbook |publisher=U.S. Geological Survey |url=https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/mineral-pubs/germanium/germamyb05.pdf |access-date=27 September 2025}}</ref>
+|-
+| 2006 ||   ||   ||   ||   || 4.6 || 100 || World total market supply (including 35 t recycling). "In 2006, production decreased, while consumption strongly rose, resulting in a deficit. Prices of germanium metal and germanium dioxide in 2007 had increased to record levels" || <ref>{{cite report |title=Germanium—2006 Minerals Yearbook |publisher=U.S. Geological Survey |url=https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/mineral-pubs/germanium/myb1-2006-germa.pdf |access-date=27 September 2025}}</ref>
+|-
+| 2007 ||   ||   ||   ||   || 4.6 || 145 || Including 6,902 kg released from the NDS. The recycling supplied about 30% of the world's total || <ref>{{cite report |title=Germanium—2007 Minerals Yearbook |publisher=U.S. Geological Survey |url=https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/mineral-pubs/germanium/myb1-2007-germa.pdf |access-date=27 September 2025}}</ref>
+|-
+| 2008 || ~100 || ~27 || ~5 || ~2 || 4.6 || ~140 || Worldwide, the vast majority of germanium production was concentrated in Canada and China || <ref>{{cite report |title=Germanium—2008 Minerals Yearbook |publisher=U.S. Geological Survey |url=https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/mineral-pubs/germanium/myb1-2008-germa.pdf |access-date=27 September 2025}}</ref><ref name ="RFCAmbrian2025"/>
+|-
+| 2009 || ~100 || ~27 || ~5 || ~2 || ~6 || 100 - 120 || Worldwide, primary germanium was recovered from copper or zinc residues or from coal in Canada (concentrates shipped from the United States), China (multiple sources), Finland (concentrates from Congo Kinshasa), and Russia (lignite coal from Sakhalin) || <ref>{{cite report |title=Germanium—2009 Minerals Yearbook |publisher=U.S. Geological Survey |url=https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/mineral-pubs/germanium/myb1-2009-germa.pdf |access-date=27 September 2025}}</ref><ref name ="RFCAmbrian2025"/>
+|-
+| 2010 || ~77 || ~15 || ~4 || ~15 || 9.3 || 100 - 120 || Other is mainly Finland || <ref>{{cite report |title=Germanium—2010 Minerals Yearbook |publisher=U.S. Geological Survey |url=https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/mineral-pubs/germanium/myb1-2010-germa.pdf |access-date=27 September 2025}}</ref><ref name ="RFCAmbrian2025"/>
+|-
+| 2013 || ~107 || ~20 || ~4 || ~21 || ~4 || ~155 || Other is mainly Finland || <ref>{{cite report |title=Germanium—2013 Minerals Yearbook (Advance Release) |publisher=U.S. Geological Survey |year=2015 |url=https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/mineral-pubs/germanium/myb1-2013-germa.pdf |access-date=27 September 2025}}</ref><ref name ="RFCAmbrian2025"/>
+|-
+| 2017 || 79.1 || ~35 || 5.0 || ~1 || ~4 || 124 ||  || <ref name = "USGS2021">{{cite report |title=Germanium—2021 Minerals Yearbook |publisher=U.S. Geological Survey |date=23 June 2025 |url=https://pubs.usgs.gov/myb/vol1/2021/myb1-2021-germanium.pdf |access-date=27 September 2025}}</ref><ref name ="RFCAmbrian2025"/>
+|-
+| 2020 || 95 - 105 || ~24 || 5.0 || ~3 || ~2 || 140 ||  || <ref name = "USGS2021"/><ref name ="RFCAmbrian2025"/>
+|-
+| 2023 || ~200 || ~27 || ~7 || ~3 || ~2 || 243 || "These estimates include both primary and secondary production." || <ref name ="RFCAmbrian2025">{{cite report |title=Germanium Report |publisher=RFC Ambrian |date=April 2025 |url=https://www.rfcambrian.com/wp-content/uploads/2025/04/rfc-ambrian-germanium-report-april-2025.pdf |access-date=27 September 2025}}</ref>
+|}
 == Applications ==
+{{Pie chart
+ | caption = Germanium usage (2023)<ref name ="RFCAmbrian2025"/>
+ | label1 = Fibre optics | value1 = 26 | color1 = #0b88d4
+ | label2 = Infrared optics | value2 = 22 | color2 = #0b6d3a
+ | label3 = PET catalyst | value3 = 20 | color3 = #0a4777
+ | label4 = Electronics | value4 = 12 | color4 = #7fba39
+ | label5 = Solar | value5 = 10 | color5 = #c8b89b
+ | label6 = Gamma ray detectors | value6 = 5  | color6 = #48c1b5
+ | label7 = Other | value7 = 5 | color7 = #cfd2d4
+}}
 The major global end uses for germanium were electronics and solar applications, fiber-optic systems, infrared optics, and polymerization catalysts. Other uses included chemotherapy, metallurgy, and phosphors.<ref>{{Cite web |last=Mineral |first=Commodity |date=January 4, 2024 |title=Mineral Commodity Summaries 2024 |url=https://pubs.usgs.gov/periodicals/mcs2024/mcs2024-germanium.pdf |access-date=May 14, 2025 |website=Mineral Commodity}}</ref>
@@ Line 181: / Line 240: @@
      |Jacket 400&nbsp;µm
 }}]]
-The notable properties of [[Germanium dioxide|germania]] (GeO<sub>2</sub>) are its high [[refractive index|index of refraction]] and its low [[Dispersion (optics)|optical dispersion]]. These make it especially useful for [[wide-angle camera lens]]es, [[microscopy]], and the core part of [[optical fiber]]s.<ref>{{cite journal |title=Infrared Detector Arrays for Astronomy |journal=Annual Review of Astronomy and Astrophysics |date=2007 |doi=10.1146/annurev.astro.44.051905.092436 |last=Rieke |first=G. H. |s2cid=26285029 |volume=45 |issue=1 |pages=77–115 |bibcode=2007ARA&A..45...77R}}</ref><ref name="Brown">{{cite web |url=http://minerals.usgs.gov/minerals/pubs/commodity/germanium/220400.pdf |title=Germanium |first=Robert D. Jr. |last=Brown |publisher=U.S. Geological Survey |year=2000 |access-date=2008-09-22 |archive-date=2011-06-08 |archive-url=https://web.archive.org/web/20110608071221/http://minerals.usgs.gov/minerals/pubs/commodity/germanium/220400.pdf |url-status=live}}</ref> It has replaced [[titanium dioxide|titania]] as the [[dopant]] for silica fiber, eliminating the subsequent heat treatment that made the fibers brittle.<ref>{{cite web |url=http://ptgmedia.pearsoncmg.com/images/1587051052/samplechapter/1587051052content.pdf |title=Chapter III: Optical Fiber For Communications |publisher=Stanford Research Institute |access-date=2008-08-22 |archive-date=2014-12-05 |archive-url=https://web.archive.org/web/20141205210827/http://ptgmedia.pearsoncmg.com/images/1587051052/samplechapter/1587051052content.pdf |url-status=live}}</ref> At the end of 2002, the fiber optics industry consumed 60% of the annual germanium use in the United States, but this is less than 10% of worldwide consumption.<ref name="Brown" /> [[GeSbTe]] is a [[phase change material]] used for its optic properties, such as that used in [[DVD-RW|rewritable DVDs]].<ref>{{cite web |url=http://www.osta.org/technology/pdf/dvdqa.pdf |archive-url=https://web.archive.org/web/20090419202545/http://www.osta.org/technology/pdf/dvdqa.pdf |archive-date=2009-04-19 |title=Understanding Recordable & Rewritable DVD |edition=First |access-date=2008-09-22 |publisher=Optical Storage Technology Association (OSTA)}}</ref>
+The notable properties of [[Germanium dioxide|germania]] (GeO<sub>2</sub>) are its high [[refractive index|index of refraction]] and its low [[Dispersion (optics)|optical dispersion]]. These make it especially useful for [[wide-angle camera lens]]es, [[microscopy]], and the core part of [[optical fiber]]s.<ref>{{cite journal |title=Infrared Detector Arrays for Astronomy |journal=Annual Review of Astronomy and Astrophysics |date=2007 |doi=10.1146/annurev.astro.44.051905.092436 |last=Rieke |first=G. H. |s2cid=26285029 |volume=45 |issue=1 |pages=77–115 |bibcode=2007ARA&A..45...77R}}</ref><ref name="Brown">{{cite web |url=https://minerals.usgs.gov/minerals/pubs/commodity/germanium/220400.pdf |title=Germanium |first=Robert D. Jr. |last=Brown |publisher=U.S. Geological Survey |year=2000 |access-date=2008-09-22 |archive-date=2011-06-08 |archive-url=https://web.archive.org/web/20110608071221/http://minerals.usgs.gov/minerals/pubs/commodity/germanium/220400.pdf |url-status=live}}</ref> It has replaced [[titanium dioxide|titania]] as the [[dopant]] for silica fiber, eliminating the subsequent heat treatment that made the fibers brittle.<ref>{{cite web |url=http://ptgmedia.pearsoncmg.com/images/1587051052/samplechapter/1587051052content.pdf |title=Chapter III: Optical Fiber For Communications |publisher=Stanford Research Institute |access-date=2008-08-22 |archive-date=2014-12-05 |archive-url=https://web.archive.org/web/20141205210827/http://ptgmedia.pearsoncmg.com/images/1587051052/samplechapter/1587051052content.pdf |url-status=live}}</ref> At the end of 2002, the fiber optics industry consumed 60% of the annual germanium use in the United States, but this is less than 10% of worldwide consumption.<ref name="Brown" /> [[GeSbTe]] is a [[phase change material]] used for its optic properties, such as that used in [[DVD-RW|rewritable DVDs]].<ref>{{cite web |url=http://www.osta.org/technology/pdf/dvdqa.pdf |archive-url=https://web.archive.org/web/20090419202545/http://www.osta.org/technology/pdf/dvdqa.pdf |archive-date=2009-04-19 |title=Understanding Recordable & Rewritable DVD |edition=First |access-date=2008-09-22 |publisher=Optical Storage Technology Association (OSTA)}}</ref>
 Because germanium is transparent in the infrared wavelengths, it is an important [[infrared]] optical material that can be readily cut and polished into lenses and windows. It is especially used as the front optic in [[Thermographic camera|thermal imaging cameras]] working in the 8 to 14&nbsp;[[micrometre|micron]] range for passive thermal imaging and for hot-spot detection in military, mobile [[night vision]], and fire fighting applications.<ref name="Moska" /> It is used in infrared [[spectroscope]]s and other optical equipment that require extremely sensitive [[thermography|infrared detectors]].<ref name="Brown" /> It has a very high [[refractive index]] (4.0) and must be coated with anti-reflection agents. Particularly, a very hard special antireflection coating of [[diamond-like carbon]] (DLC), refractive index 2.0, is a good match and produces a diamond-hard surface that can withstand much environmental abuse.<ref>{{cite journal |first=Alan H. |last=Lettington |doi=10.1016/S0008-6223(98)00062-1 |title=Applications of diamond-like carbon thin films |volume=36 |issue=5–6 |date=1998 |pages=555–560 |journal=Carbon |bibcode=1998Carbo..36..555L}}</ref><ref>{{cite journal |first=Michael N. |last=Gardos |author2=Bonnie L. Soriano |author3=Steven H. Propst |title=Study on correlating rain erosion resistance with sliding abrasion resistance of DLC on germanium |journal=Proc. SPIE |volume=1325 |page=99 |date=1990 |doi=10.1117/12.22449 |issue=Mechanical Properties |series=SPIE Proceedings |editor1-last=Feldman |editor1-first=Albert |editor2-last=Holly |editor2-first=Sandor |bibcode=1990SPIE.1325...99G |s2cid=137425193}}</ref>
@@ Line 192: / Line 251: @@
 Germanium-on-insulator (GeOI) substrates are seen as a potential replacement for silicon on miniaturized chips.<ref name="usgs" /> CMOS circuit based on GeOI substrates has been reported recently.<ref>{{cite journal |first1=Heng |last1=Wu |first2=Peide D. |last2=Ye |date=August 2016 |title=Fully Depleted Ge CMOS Devices and Logic Circuits on Si |journal=[[IEEE Transactions on Electron Devices]] |volume=63 |issue=8 |pages=3028–3035 |doi=10.1109/TED.2016.2581203 |bibcode=2016ITED...63.3028W |s2cid=3231511 |url=https://engineering.purdue.edu/~yep/Papers/TED_Ge%20Fully%20Depleted%20CMOS_2016.pdf |access-date=2019-03-04 |archive-date=2019-03-06 |archive-url=https://web.archive.org/web/20190306044456/https://engineering.purdue.edu/~yep/Papers/TED_Ge%20Fully%20Depleted%20CMOS_2016.pdf |url-status=live}}</ref> Other uses in electronics include [[phosphor]]s in [[fluorescent lamp]]s<ref name="lanl" /> and solid-state light-emitting diodes (LEDs).<ref name="usgs" /> Germanium transistors are still used in some [[effects pedal]]s by musicians who wish to reproduce the distinctive tonal character of the [[Distortion (music)|"fuzz"-tone]] from the early [[rock and roll]] era, most notably the [[Fuzz Face|Dallas Arbiter Fuzz Face]].<ref>{{cite journal |author=Szweda, Roy |date=2005 |title=Germanium phoenix |journal=[[III-Vs Review]] |volume=18 |issue=7 |page=55 |doi=10.1016/S0961-1290(05)71310-7}}</ref>
-Germanium has been studied as a potential material for implantable bioelectronic sensors that are [[Biodegradable electronics|resorbed]] in the body without generating harmful hydrogen gas, replacing [[zinc oxide]]- and [[indium gallium zinc oxide]]-based implementations.<ref>{{ cite journal |last1=Zhao |first1=H. |last2=Xue |first2=Z. |last3=Wu |first3=X. |display-authors=2 |date=21 July 2022 |title=Biodegradable germanium electronics for integrated biosensing of physiological signals. |journal=npj Flexible Electronics |volume=6 |at=63 |doi=10.1038/s41528-022-00196-2 |s2cid=250702946 |doi-access=free}}</ref>
+Germanium has been studied as a potential material for implantable bioelectronic sensors that are [[Biodegradable electronics|resorbed]] in the body without generating harmful hydrogen gas, replacing [[zinc oxide]]- and [[indium gallium zinc oxide]]-based implementations.<ref>{{ cite journal |last1=Zhao |first1=H. |last2=Xue |first2=Z. |last3=Wu |first3=X. |display-authors=2 |date=21 July 2022 |title=Biodegradable germanium electronics for integrated biosensing of physiological signals. |journal=npj Flexible Electronics |volume=6 |article-number=63 |doi=10.1038/s41528-022-00196-2 |s2cid=250702946 |doi-access=free}}</ref>
 Germanium was also used to create many of the circuits found in some of the very first pieces of electronic musical gear, initially 1950s, primarily in early transistor-based circuits. The first guitar effects pedals in the 1960s – Fuzz pedals like the Maestro FZ-1 (1962), Dallas-Arbiter Fuzz Face (1966), and Tone Bender (1965) - used germanium transistors.<ref>{{Cite web |last=joe |date=2012-01-03 |title=The Germanium Mystique |url=https://tonefiend.com/diy/the-germanium-mystique/ |access-date=2025-02-21 |website=tonefiend.com |language=en-US}}</ref> Silicon diodes are more frequently used in more modern equipment, but germanium diodes are still used in some applications as they have lower barrier potential and smoother [[transconductance]] curves, leading to less harsh [[Clipping (audio)|clipping]].<ref>{{Citation |last=Dailey |first=Denton J. |title=Guitar Effects Circuits |date=2013 |work=Electronics for Guitarists |pages=199–200 |url=https://link.springer.com/chapter/10.1007/978-1-4614-4087-1_5 |access-date=2025-02-21 |place=New York, NY |publisher=Springer New York |language=en |doi=10.1007/978-1-4614-4087-1_5 |isbn=978-1-4614-4086-4|url-access=subscription }}</ref>
@@ Line 204: / Line 263: @@
 In recent years germanium has seen increasing use in precious metal alloys. In [[sterling silver]] alloys, for instance, it reduces [[firescale]], increases tarnish resistance, and improves precipitation hardening. A tarnish-proof silver alloy trademarked [[Argentium sterling silver|Argentium]] contains 1.2% germanium.<ref name="usgs" />
-[[Semiconductor detector#Germanium detectors|Semiconductor detectors]] made of single crystal high-purity germanium can precisely identify radiation sources—for example in airport security.<ref>{{cite web |title=Performance of Light-Weight, Battery-Operated, High Purity Germanium Detectors for Field Use |first1=Ronald |last1=Keyser |last2=Twomey |first2=Timothy |last3=Upp |first3=Daniel |url=http://www.ortec-online.com/papers/inmm_2003_keyser.pdf |access-date=2008-09-06 |publisher=Oak Ridge Technical Enterprise Corporation (ORTEC) |archive-url=https://web.archive.org/web/20071026162911/http://www.ortec-online.com/papers/inmm_2003_keyser.pdf |archive-date=October 26, 2007 |url-status=dead}}</ref> Germanium is useful for [[Crystal monochromator|monochromators]] for [[beamline]]s used in [[single crystal]] [[neutron scattering]] and [[Synchrotron light|synchrotron X-ray]] diffraction. The reflectivity has advantages over silicon in neutron and [[High energy X-rays|high energy X-ray]] applications.<ref>{{cite journal |doi=10.1142/S0218301396000062 |date=1996 |journal=International Journal of Modern Physics E |volume=5 |issue=1 |pages=131–151 |title=Optimization of Germanium for Neutron Diffractometers |bibcode=1996IJMPE...5..131A |last1=Ahmed |first1=F. U. |last2=Yunus |first2=S. M. |last3=Kamal |first3=I. |last4=Begum |first4=S. |last5=Khan |first5=Aysha A. |last6=Ahsan |first6=M. H. |last7=Ahmad |first7=A. A. Z.}}</ref> Crystals of high purity germanium are used in detectors for [[gamma spectroscopy]] and the search for [[dark matter]].<ref>{{cite journal |doi=10.1016/j.nuclphysa.2005.02.155 |title=Astrophysical constraints from gamma-ray spectroscopy |date=2006 |last1=Diehl |first1=R. |journal=Nuclear Physics A |volume=777 |issue=2006 |pages=70–97 |last2=Prantzos |first2=N. |last3=Vonballmoos |first3=P. |arxiv=astro-ph/0502324 |bibcode=2006NuPhA.777...70D |citeseerx=10.1.1.256.9318 |s2cid=2360391}}</ref> Germanium crystals are also used in X-ray spectrometers for the determination of phosphorus, chlorine and sulfur.<ref>Eugene P. Bertin (1970). ''Principles and practice of X-ray spectrometric analysis'', Chapter 5.4 – Analyzer crystals, Table 5.1, p. 123; Plenum Press</ref>
+[[Semiconductor detector#Germanium detectors|Semiconductor detectors]] made of single crystal high-purity germanium can precisely identify radiation sources—for example in airport security.<ref>{{cite web |title=Performance of Light-Weight, Battery-Operated, High Purity Germanium Detectors for Field Use |first1=Ronald |last1=Keyser |last2=Twomey |first2=Timothy |last3=Upp |first3=Daniel |url=http://www.ortec-online.com/papers/inmm_2003_keyser.pdf |access-date=2008-09-06 |publisher=Oak Ridge Technical Enterprise Corporation (ORTEC) |archive-url=https://web.archive.org/web/20071026162911/http://www.ortec-online.com/papers/inmm_2003_keyser.pdf |archive-date=October 26, 2007 }}</ref> Germanium is useful for [[Crystal monochromator|monochromators]] for [[beamline]]s used in [[single crystal]] [[neutron scattering]] and [[Synchrotron light|synchrotron X-ray]] diffraction. The reflectivity has advantages over silicon in neutron and [[High energy X-rays|high energy X-ray]] applications.<ref>{{cite journal |doi=10.1142/S0218301396000062 |date=1996 |journal=International Journal of Modern Physics E |volume=5 |issue=1 |pages=131–151 |title=Optimization of Germanium for Neutron Diffractometers |bibcode=1996IJMPE...5..131A |last1=Ahmed |first1=F. U. |last2=Yunus |first2=S. M. |last3=Kamal |first3=I. |last4=Begum |first4=S. |last5=Khan |first5=Aysha A. |last6=Ahsan |first6=M. H. |last7=Ahmad |first7=A. A. Z.}}</ref> Crystals of high purity germanium are used in detectors for [[gamma spectroscopy]] and the search for [[dark matter]].<ref>{{cite journal |doi=10.1016/j.nuclphysa.2005.02.155 |title=Astrophysical constraints from gamma-ray spectroscopy |date=2006 |last1=Diehl |first1=R. |journal=Nuclear Physics A |volume=777 |issue=2006 |pages=70–97 |last2=Prantzos |first2=N. |last3=Vonballmoos |first3=P. |arxiv=astro-ph/0502324 |bibcode=2006NuPhA.777...70D |citeseerx=10.1.1.256.9318 |s2cid=2360391}}</ref> Germanium crystals are also used in X-ray spectrometers for the determination of phosphorus, chlorine and sulfur.<ref>Eugene P. Bertin (1970). ''Principles and practice of X-ray spectrometric analysis'', Chapter 5.4 – Analyzer crystals, Table 5.1, p. 123; Plenum Press</ref>
-Germanium is emerging as an important material for [[spintronics]] and spin-based [[quantum computing]] applications. In 2010, researchers demonstrated room temperature spin transport<ref>{{Cite journal |last1=Shen |first1=C. |last2=Trypiniotis |first2=T. |last3=Lee |first3=K. Y. |last4=Holmes |first4=S. N. |last5=Mansell |first5=R. |last6=Husain |first6=M. |last7=Shah |first7=V. |last8=Li |first8=X. V. |last9=Kurebayashi |first9=H. |date=2010-10-18 |title=Spin transport in germanium at room temperature |journal=Applied Physics Letters |volume=97 |issue=16 |page=162104 |doi=10.1063/1.3505337 |issn=0003-6951 |bibcode=2010ApPhL..97p2104S |url=https://eprints.soton.ac.uk/271616/1/Gespin.pdf |access-date=2018-11-16 |archive-date=2017-09-22 |archive-url=https://web.archive.org/web/20170922180043/https://eprints.soton.ac.uk/271616/1/Gespin.pdf |url-status=live}}</ref> and more recently donor electron spins in germanium has been shown to have very long [[coherence time]]s.<ref>{{Cite journal |last1=Sigillito |first1=A. J. |last2=Jock |first2=R. M. |last3=Tyryshkin |first3=A. M. |last4=Beeman |first4=J. W. |last5=Haller |first5=E. E. |last6=Itoh |first6=K. M. |last7=Lyon |first7=S. A. |date=2015-12-07 |title=Electron Spin Coherence of Shallow Donors in Natural and Isotopically Enriched Germanium |journal=Physical Review Letters |volume=115 |issue=24 |pages=247601 |doi=10.1103/PhysRevLett.115.247601 |pmid=26705654 |arxiv=1506.05767 |bibcode=2015PhRvL.115x7601S |s2cid=13299377}}</ref>
+Germanium is emerging as an important material for [[spintronics]] and spin-based [[quantum computing]] applications. In 2010, researchers demonstrated room temperature spin transport<ref>{{Cite journal |last1=Shen |first1=C. |last2=Trypiniotis |first2=T. |last3=Lee |first3=K. Y. |last4=Holmes |first4=S. N. |last5=Mansell |first5=R. |last6=Husain |first6=M. |last7=Shah |first7=V. |last8=Li |first8=X. V. |last9=Kurebayashi |first9=H. |date=2010-10-18 |title=Spin transport in germanium at room temperature |journal=Applied Physics Letters |volume=97 |issue=16 |page=162104 |doi=10.1063/1.3505337 |issn=0003-6951 |bibcode=2010ApPhL..97p2104S |url=https://eprints.soton.ac.uk/271616/1/Gespin.pdf |access-date=2018-11-16 |archive-date=2017-09-22 |archive-url=https://web.archive.org/web/20170922180043/https://eprints.soton.ac.uk/271616/1/Gespin.pdf |url-status=live}}</ref> and more recently donor electron spins in germanium has been shown to have very long [[coherence time]]s.<ref>{{Cite journal |last1=Sigillito |first1=A. J. |last2=Jock |first2=R. M. |last3=Tyryshkin |first3=A. M. |last4=Beeman |first4=J. W. |last5=Haller |first5=E. E. |last6=Itoh |first6=K. M. |last7=Lyon |first7=S. A. |date=2015-12-07 |title=Electron Spin Coherence of Shallow Donors in Natural and Isotopically Enriched Germanium |journal=Physical Review Letters |volume=115 |issue=24 |article-number=247601 |doi=10.1103/PhysRevLett.115.247601 |pmid=26705654 |arxiv=1506.05767 |bibcode=2015PhRvL.115x7601S |s2cid=13299377}}</ref>
 == Germanium and health ==
-Germanium is not considered essential to the health of plants or animals.<ref name="American Cancer Society" /> Germanium in the environment has little or no health impact. This is primarily because it usually occurs only as a trace element in ores and [[carbon]]aceous materials, and the various industrial and electronic applications involve very small quantities that are not likely to be ingested.<ref name="usgs" /> For similar reasons, end-use germanium has little impact on the environment as a biohazard. Some reactive intermediate compounds of germanium are poisonous (see precautions, below).<ref name="Brown Jr">{{cite report |url=http://minerals.usgs.gov/minerals/pubs/commodity/germanium/220798.pdf |publisher=US Geological Surveys |access-date=2008-09-09 |title=Commodity Survey:Germanium |first=Robert D. Jr. |last=Brown |date= |archive-date=2018-03-04 |archive-url=https://web.archive.org/web/20180304113236/https://minerals.usgs.gov/minerals/pubs/commodity/germanium/220798.pdf |url-status=live}}</ref>
+Germanium is not considered essential to the health of plants or animals.<ref name="American Cancer Society" /> Germanium in the environment has little or no health impact. This is primarily because it usually occurs only as a trace element in ores and [[carbon]]aceous materials, and the various industrial and electronic applications involve very small quantities that are not likely to be ingested.<ref name="usgs" /> For similar reasons, end-use germanium has little impact on the environment as a biohazard. Some reactive intermediate compounds of germanium are poisonous (see precautions, below).<ref name="Brown Jr">{{cite report |url=https://minerals.usgs.gov/minerals/pubs/commodity/germanium/220798.pdf |publisher=US Geological Surveys |access-date=2008-09-09 |title=Commodity Survey:Germanium |first=Robert D. Jr. |last=Brown |date= |archive-date=2018-03-04 |archive-url=https://web.archive.org/web/20180304113236/https://minerals.usgs.gov/minerals/pubs/commodity/germanium/220798.pdf |url-status=live}}</ref>
-Germanium supplements, made from both organic and inorganic germanium, have been marketed as an [[alternative medicine]] capable of treating [[leukemia]] and [[lung cancer]].<ref name="acs" /> There is, however, no [[evidence-based medicine|medical evidence]] of benefit; some evidence suggests that such supplements are actively harmful.<ref name="American Cancer Society">{{cite book |publisher=American Cancer Society |title=American Cancer Society Complete Guide to Complementary and Alternative Cancer Therapies |edition=2nd |year=2009 |isbn=978-0944235713 |editor=Ades TB |pages=[https://archive.org/details/americancancerso0000unse/page/360 360–363] |chapter=Germanium |chapter-url=https://archive.org/details/americancancerso0000unse/page/360}}</ref> [[U.S. Food and Drug Administration]] (FDA) research has concluded that inorganic germanium, when used as a [[nutritional supplement]], "presents potential human [[health hazard]]".<ref name="toxic">{{cite journal |last=Tao |first=S. H. |author2=Bolger, P. M. |date=June 1997 |title=Hazard Assessment of Germanium Supplements |journal=[[Regulatory Toxicology and Pharmacology]] |volume=25 |issue=3 |pages=211–219 |doi=10.1006/rtph.1997.1098 |pmid=9237323 |url=https://zenodo.org/record/1229957 |access-date=2019-06-30 |archive-date=2020-03-10 |archive-url=https://web.archive.org/web/20200310041729/https://zenodo.org/record/1229957 |url-status=live}}</ref>
+Germanium supplements, made from both organic and inorganic germanium, have been marketed as an [[alternative medicine]] capable of treating [[leukemia]] and [[lung cancer]].<ref name="acs" /> There is, however, no [[evidence-based medicine|medical evidence]] of benefit; some evidence suggests that such supplements are actively harmful.<ref name="American Cancer Society">{{cite book |publisher=American Cancer Society |title=American Cancer Society Complete Guide to Complementary and Alternative Cancer Therapies |edition=2nd |year=2009 |isbn=978-0-944235-71-3 |editor=Ades TB |pages=[https://archive.org/details/americancancerso0000unse/page/360 360–363] |chapter=Germanium |chapter-url=https://archive.org/details/americancancerso0000unse/page/360}}</ref> [[U.S. Food and Drug Administration]] (FDA) research has concluded that inorganic germanium, when used as a [[nutritional supplement]], "presents potential human [[health hazard]]".<ref name="toxic">{{cite journal |last=Tao |first=S. H. |author2=Bolger, P. M. |date=June 1997 |title=Hazard Assessment of Germanium Supplements |journal=[[Regulatory Toxicology and Pharmacology]] |volume=25 |issue=3 |pages=211–219 |doi=10.1006/rtph.1997.1098 |pmid=9237323 |url=https://zenodo.org/record/1229957 |access-date=2019-06-30 |archive-date=2020-03-10 |archive-url=https://web.archive.org/web/20200310041729/https://zenodo.org/record/1229957 |url-status=live}}</ref>
 Some germanium compounds have been administered by alternative medical practitioners as non-FDA-allowed injectable solutions. Soluble inorganic forms of germanium used at first, notably the citrate-lactate salt, resulted in some cases of [[renal]] dysfunction, [[hepatic steatosis]], and peripheral [[neuropathy]] in individuals using them over a long term. Plasma and urine germanium concentrations in these individuals, several of whom died, were several orders of magnitude greater than [[endogenous]] levels. A more recent organic form, beta-carboxyethylgermanium sesquioxide ([[propagermanium]]), has not exhibited the same spectrum of toxic effects.<ref>{{cite book |author=Baselt, R. |title=Disposition of Toxic Drugs and Chemicals in Man |edition=8th |publisher=Biomedical Publications |place=Foster City, CA |date=2008 |pages=693–694}}</ref>
@@ Line 234: / Line 293: @@
 {{EB1911 poster|Germanium}}
 * [http://www.periodicvideos.com/videos/032.htm Germanium] at ''[[The Periodic Table of Videos]]'' (University of Nottingham)
+* [[usgs.gov]] (Mineral Commodity Summaries 2025): [https://pubs.usgs.gov/periodicals/mcs2025/mcs2025.pdf#page=80 Germanium]
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Germanium: Difference between revisions

Latest revision as of 08:48, 16 November 2025

Contents

History

Characteristics

Chemistry

Isotopes

Occurrence

Production

Production by country

Applications

Optics

Electronics

Other uses

Germanium and health

Precautions for chemically reactive germanium compounds

See also

Notes

References

External links

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Germanium: Difference between revisions

Latest revision as of 08:48, 16 November 2025

History

Characteristics

Chemistry

Isotopes

Occurrence

Production

Production by country

Applications

Optics

Electronics

Other uses

Germanium and health

Precautions for chemically reactive germanium compounds

See also

Notes

References

External links

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