Pyrite: Difference between revisions

Latest revision as of 05:00, 15 November 2025

Template:Short description Script error: No such module "redirect hatnote". Script error: No such module "about".

Template:Infobox mineral

The mineral pyrite (Template:IPAc-en Template:Respell),^[1] or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Fe S₂ (iron (II) disulfide). Pyrite is the most abundant sulfide mineral.^[2]

File:2780M-pyrite1.jpg

Pyrite cubic crystals on marl from Navajún, La Rioja, Spain (size: Template:Convert, Template:Convert; main crystal: Template:Convert on edge)

Pyrite's metallic luster and pale brass-yellow hue give it a superficial resemblance to gold, hence the well-known nickname of fool's gold. The color has also led to the nicknames brass, brazzle, and brazil, primarily used to refer to pyrite found in coal.^[3]^[4]

The name pyrite is derived from the Greek Script error: No such module "Lang". (Script error: No such module "Lang".), 'stone or mineral which strikes fire',^[5] in turn from Script error: No such module "Lang". (Script error: No such module "Lang".), 'fire'.^[6] In ancient Roman times, this name was applied to several types of stone that would create sparks when struck against steel; Pliny the Elder described one of them as being brassy, almost certainly a reference to what is now called pyrite.^[7]

By Georgius Agricola's time, Template:Circa, the term had become a generic term for all of the sulfide minerals.^[8]

File:Pyrite under Normal and Polarized light.jpg

Pyrite under normal and polarized light

Pyrite is usually found associated with other sulfides or oxides in quartz veins, sedimentary rock, and metamorphic rock, as well as in coal beds and as a replacement mineral in fossils, but has also been identified in the sclerites of scaly-foot gastropods.^[9] Despite being nicknamed "fool's gold", pyrite is sometimes found in association with small quantities of gold. A substantial proportion of the gold is "invisible gold" incorporated into the pyrite. It has been suggested that the presence of both gold and arsenic is a case of coupled substitution but as of 1997 the chemical state of the gold remained controversial.^[10]

Uses

File:Stolna pri Perneku.jpg

An abandoned pyrite mine near Pernek in Slovakia

Pyrite gained a brief popularity in the 16th and 17th centuries as a source of ignition in early firearms, most notably the wheellock, where a sample of pyrite was placed against a circular file to strike the sparks needed to fire the gun.^[11]

Pyrite is used with flintstone and a form of tinder made of stringybark by the Kaurna people of South Australia, as a traditional method of starting fires.^[12]

Pyrite has been used since classical times to manufacture copperas (ferrous sulfate). Iron pyrite was heaped up and allowed to weather (an example of an early form of heap leaching). The acidic runoff from the heap was then boiled with iron to produce iron sulfate. In the 15th century, new methods of such leaching began to replace the burning of sulfur as a source of sulfuric acid. By the 19th century, it had become the dominant method.^[13]

Pyrite remains in commercial use for the production of sulfur dioxide, for use in such applications as the paper industry, and in the manufacture of sulfuric acid. Thermal decomposition of pyrite into FeS (iron(II) sulfide) and elemental sulfur starts at Template:Cvt; at around Template:Cvt, p_S₂ is about 1 atm.^[14]

A newer commercial use for pyrite is as the cathode material in Energizer brand non-rechargeable lithium metal batteries.^[15]

Pyrite is a semiconductor material with a band gap of 0.95 eV.^[16] Pure pyrite is naturally n-type, in both crystal and thin-film forms, potentially due to sulfur vacancies in the pyrite crystal structure acting as n-dopants.^[17]

During the early years of the 20th century, pyrite was used as a mineral detector in radio receivers, and is still used by crystal radio hobbyists. Until the vacuum tube matured, the crystal detector was the most sensitive and dependable detector available—with considerable variation between mineral types and even individual samples within a particular type of mineral. Pyrite detectors occupied a midway point between galena detectors and the more mechanically complicated perikon mineral pairs. Pyrite detectors can be as sensitive as a modern 1N34A germanium diode detector.^[18]^[19]

Pyrite has been proposed as an abundant, non-toxic, inexpensive material in low-cost photovoltaic solar panels.^[20] Synthetic iron sulfide was used with copper sulfide to create the photovoltaic material.^[21] More recent efforts are working toward thin-film solar cells made entirely of pyrite.^[17]

Pyrite is used to make marcasite jewelry. Marcasite jewelry, using small faceted pieces of pyrite, often set in silver, has been made since ancient times and was popular in the Victorian era.^[22] At the time when the term became common in jewelry making, "marcasite" referred to all iron sulfides including pyrite, and not to the orthorhombic FeS₂ mineral marcasite which is lighter in color, brittle and chemically unstable, and thus not suitable for jewelry making. Marcasite jewelry does not actually contain the mineral marcasite. The specimens of pyrite, when it appears as good quality crystals, are used in decoration. They are also very popular in mineral collecting. Among the sites that provide the best specimens are Soria and La Rioja provinces (Spain).^[23]

In value terms, China ($47 million) constitutes the largest market for imported unroasted iron pyrites worldwide, making up 65% of global imports. China is also the fastest growing in terms of the unroasted iron pyrites imports, with a CAGR of +27.8% from 2007 to 2016.^[24]

Research

In July 2020 scientists reported that they have observed a voltage-induced transformation of normally diamagnetic pyrite into a ferromagnetic material, which may lead to applications in devices such as solar cells or magnetic data storage.^[25]^[26]

Researchers at Trinity College Dublin, Ireland have demonstrated that FeS₂ can be exfoliated into few-layers just like other two-dimensional layered materials such as graphene by a simple liquid-phase exfoliation route. This is the first study to demonstrate the production of non-layered 2D-platelets from 3D bulk FeS₂. Furthermore, they have used these 2D-platelets with 20% single walled carbon-nanotube as an anode material in lithium-ion batteries, reaching a capacity of 1000 mAh/g close to the theoretical capacity of FeS₂.^[27]

In 2021, a natural pyrite stone has been crushed and pre-treated followed by liquid-phase exfoliation into two-dimensional nanosheets, which has shown capacities of 1200 mAh/g as an anode in lithium-ion batteries.^[28]

Formal oxidation states for pyrite, marcasite, molybdenite and arsenopyrite

From the perspective of classical inorganic chemistry, which assigns formal oxidation states to each atom, pyrite and marcasite are probably best described as Fe²⁺[S₂]²⁻. This formalism recognizes that the sulfur atoms in pyrite occur in pairs with clear S–S bonds. These persulfide [⁻S–S⁻] units can be viewed as derived from hydrogen disulfide, H₂S₂. Thus pyrite would be more descriptively called iron persulfide, not iron disulfide. In contrast, molybdenite, MoS₂, features isolated sulfide S²⁻ centers and the oxidation state of molybdenum is Mo⁴⁺. The mineral arsenopyrite has the formula FeAsS. Whereas pyrite has [S₂]²⁻ units, arsenopyrite has [AsS]³⁻ units, formally derived from deprotonation of arsenothiol (H₂AsSH). Analysis of classical oxidation states would recommend the description of arsenopyrite as Fe³⁺[AsS]³⁻.^[29]

Crystallography

File:FeS2structure.png

Crystal structure of pyrite. In the center of the cell a S₂²⁻ pair is seen in yellow.

Iron-pyrite FeS₂ represents the prototype compound of the crystallographic pyrite structure. The structure is cubic and was among the first crystal structures solved by X-ray diffraction.^[30] It belongs to the crystallographic space group Pa3 and is denoted by the Strukturbericht notation C2. Under thermodynamic standard conditions the lattice constant $a$ of stoichiometric iron pyrite FeS₂ amounts to 541.87 pm.^[31] The unit cell is composed of a Fe face-centered cubic sublattice into which the Template:Chem ions are embedded. (Note though that the iron atoms in the faces are not equivalent by translation alone to the iron atoms at the corners.) The pyrite structure is also seen in other MX₂ compounds of transition metals M and chalcogens X = O, S, Se and Te. Certain dipnictides with X standing for P, As and Sb etc. are also known to adopt the pyrite structure.^[32]

The Fe atoms are bonded to six S atoms, giving a distorted octahedron. The material is a semiconductor. The Fe ions are usually considered to be low spin divalent state (as shown by Mössbauer spectroscopy as well as XPS). The material as a whole behaves as a Van Vleck paramagnet, despite its low-spin divalency.^[33]

The sulfur centers occur in pairs, described as Template:Chem.^[34] Reduction of pyrite with potassium gives potassium dithioferrate, KFeS₂. This material features ferric ions and isolated sulfide (S²⁻) centers.

The S atoms are tetrahedral, being bonded to three Fe centers and one other S atom. The site symmetry at Fe and S positions is accounted for by point symmetry groups C_3i and C₃, respectively. The missing center of inversion at S lattice sites has important consequences for the crystallographic and physical properties of iron pyrite. These consequences derive from the crystal electric field active at the sulfur lattice site, which causes a polarization of S ions in the pyrite lattice.^[35] The polarisation can be calculated on the basis of higher-order Madelung constants and has to be included in the calculation of the lattice energy by using a generalised Born–Haber cycle. This reflects the fact that the covalent bond in the sulfur pair is inadequately accounted for by a strictly ionic treatment.^[36]

Arsenopyrite has a related structure with heteroatomic As–S pairs rather than S-S pairs. Marcasite also possesses homoatomic anion pairs, but the arrangement of the metal and diatomic anions differs from that of pyrite. Despite its name, chalcopyrite (Template:Chem) does not contain dianion pairs, but single S²⁻ sulfide anions.

Crystal habit

File:Pyrite elbe.jpg

Pyritohedron-shaped crystals from Italy

Pyrite usually forms cuboid crystals, sometimes forming in close association to form raspberry-shaped masses called framboids. However, under certain circumstances, it can form anastomosing filaments or T-shaped crystals.^[37] Pyrite can also form shapes almost the same as a regular dodecahedron, known as pyritohedra, and this suggests an explanation for the artificial geometrical models found in Europe as early as the 5th century BC.^[38]Template:Clarify

Varieties

Cattierite (Co S₂), vaesite (Ni S₂) and hauerite (Mn S₂), as well as sperrylite (Pt As₂) are similar in their structure and belong also to the pyrite group.

Template:Vanchor is a nickel-cobalt bearing variety of pyrite, with > 50% substitution of Ni²⁺ for Fe²⁺ within pyrite. Bravoite is not a formally recognised mineral, and is named after the Peruvian scientist Jose J. Bravo (1874–1928).^[39]

Distinguishing similar minerals

Pyrite is distinguishable from native gold by its hardness, brittleness and crystal form. Pyrite fractures are very uneven, sometimes conchoidal because it does not cleave along a preferential plane. Native gold nuggets, or glitters, do not break but deform in a ductile way. Pyrite is brittle, gold is malleable. Natural gold tends to be anhedral (irregularly shaped without well defined faces), whereas pyrite comes as either cubes or multifaceted crystals with well developed and sharp faces easy to recognise. Well crystallised pyrite crystals are euhedral (i.e., with nice faces). Pyrite can often be distinguished by the striations which, in many cases, can be seen on its surface.

Chalcopyrite (Template:Chem2) is brighter yellow with a greenish hue when wet and is softer (3.5–4 on Mohs' scale).^[40] Arsenopyrite (FeAsS) is silver white and does not become more yellow when wet.

Hazards

File:GoldinPyriteDrainage acide.JPG

A pyrite cube (center) has dissolved away from a host rock, leaving behind trace gold

Iron pyrite is unstable when exposed to the oxidizing conditions prevailing at the Earth's surface: iron pyrite in contact with atmospheric oxygen and water, or damp, ultimately decomposes into iron oxyhydroxides (ferrihydrite, FeO(OH)) and sulfuric acid (Template:Chem). This process is accelerated by the action of Acidithiobacillus bacteria which oxidize pyrite to first produce ferrous ions (Template:Chem), sulfate ions (Template:Chem), and release protons (Template:H+, or Template:H3O+). In a second step, the ferrous ions (Template:Chem) are oxidized by Template:O2 into ferric ions (Template:Chem) which hydrolyze also releasing Template:H+ ions and producing FeO(OH). These oxidation reactions occur more rapidly when pyrite is finely dispersed (framboidal crystals initially formed by sulfate reducing bacteria (SRB) in argillaceous sediments or dust from mining operations).

Pyrite oxidation and acid mine drainage

Script error: No such module "Labelled list hatnote". Pyrite oxidation by atmospheric Template:O2 in the presence of moisture (Template:H2O) initially produces ferrous ions (Template:Chem) and sulfuric acid which dissociates into sulfate ions and protons, leading to acid mine drainage (AMD). An example of acid rock drainage caused by pyrite is the 2015 Gold King Mine waste water spill.^[41]

Template:Chem2

Dust explosions

Pyrite oxidation is sufficiently exothermic that underground coal mines in high-sulfur coal seams have occasionally had serious problems with spontaneous combustion.^[42] The solution is the use of buffer blasting and the use of various sealing or cladding agents to hermetically seal the mined-out areas to exclude oxygen.^[43]

In modern coal mines, limestone dust is sprayed onto the exposed coal surfaces to reduce the hazard of dust explosions. This has the secondary benefit of neutralizing the acid released by pyrite oxidation and therefore slowing the oxidation cycle described above, thus reducing the likelihood of spontaneous combustion. In the long term, however, oxidation continues, and the hydrated sulfates formed may exert crystallization pressure that can expand cracks in the rock and lead eventually to roof fall.^[44]

Weakened building materials

Script error: No such module "Labelled list hatnote". Building stone containing pyrite tends to stain brown as pyrite oxidizes. This problem appears to be significantly worse if any marcasite is present.^[45] The presence of pyrite in the aggregate used to make concrete can lead to severe deterioration as pyrite oxidizes.^[46] In early 2009, problems with Chinese drywall imported into the United States after Hurricane Katrina were attributed to pyrite oxidation, followed by microbial sulfate reduction which released hydrogen sulfide gas (Template:H2S). These problems included a foul odor and corrosion of copper wiring.^[47] In the United States, in Canada,^[48] and more recently in Ireland,^[49]^[50]^[51] where it was used as underfloor infill, pyrite contamination has caused major structural damage. Concrete exposed to sulfate ions, or sulfuric acid, degrades by sulfate attack: the formation of expansive mineral phases, such as ettringite (small needle crystals exerting a huge crystallization pressure inside the concrete pores) and gypsum creates inner tensile forces in the concrete matrix which destroy the hardened cement paste, form cracks and fissures in concrete, and can lead to the ultimate ruin of the structure. Normalized tests for construction aggregate^[52] certify such materials as free of pyrite or marcasite.

Occurrence

Pyrite is the most common of sulfide minerals and is widespread in igneous, metamorphic, and sedimentary rocks. It is a common accessory mineral in igneous rocks, where it also occasionally occurs as larger masses arising from an immiscible sulfide phase in the original magma. It is found in metamorphic rocks as a product of contact metamorphism. It also forms as a high-temperature hydrothermal mineral, though it occasionally forms at lower temperatures.^[53]

Pyrite occurs both as a primary mineral, present in the original sediments, and as a secondary mineral, deposited during diagenesis.^[53] Pyrite and marcasite commonly occur as replacement pseudomorphs after fossils in black shale and other sedimentary rocks formed under reducing environmental conditions.^[54] Pyrite is common as an accessory mineral in shale, where it is formed by precipitation from anoxic seawater, and coal beds often contain significant pyrite.^[55]

Notable deposits are found as lenticular masses in Virginia, U.S., and in smaller quantities in many other locations. Large deposits are mined at Rio Tinto in Spain and elsewhere in the Iberian Peninsula.^[56]

Cultural beliefs

In the beliefs of the Thai people (especially those in the south), pyrite is known as Khao tok Phra Ruang, Khao khon bat Phra Ruang (ข้าวตอกพระร่วง, ข้าวก้นบาตรพระร่วง) or Phet na tang, Hin na tang (เพชรหน้าทั่ง, หินหน้าทั่ง)Template:Clarify. It is believed to be a sacred item that has the power to prevent evil, black magic or demons.^[57]^[58]

Gallery

Pyrite as a replacement mineral in an ammonite from France

Pyrite as a replacement mineral in an ammonite from France
Pyrite from Ampliación a Victoria Mine, Navajún, La Rioja, Spain

Pyrite from Ampliación a Victoria Mine, Navajún, La Rioja, Spain
Pyrite from the Sweet Home Mine, with golden striated cubes intergrown with minor tetrahedrite, on a bed of transparent quartz needles

Pyrite from the Sweet Home Mine, with golden striated cubes intergrown with minor tetrahedrite, on a bed of transparent quartz needles
Radiating form of pyrite

Radiating form of pyrite
Paraspirifer bownockeri in pyrite

Paraspirifer bownockeri in pyrite
Pink fluorite perched between pyrite (left) and metallic galena (right)

Pink fluorite perched between pyrite (left) and metallic galena (right)
SEM image of intergrowth of pyrite cuboctahedral crystals (yellow) and pyrrhotite (pinkish yellow)

SEM image of intergrowth of pyrite cuboctahedral crystals (yellow) and pyrrhotite (pinkish yellow)

References

Template:Reflist

External links

Template:Sister project

Pyrite.Virtual Museum of Mineralogy. Universidad de Zaragoza, Spain
Educational article about the famous pyrite crystals from the Navajun Mine
How Minerals Form and Change "Pyrite oxidation under room conditions".
Script error: No such module "citation/CS1".

Template:Sulfur compounds Template:Disulfides Template:Authority control

↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Template:LSJ.
↑ Template:LSJ.
↑ Script error: No such module "citation/CS1".
↑ Template:Cite magazine
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ ^a ^b Script error: No such module "Citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ The pyritohedral form is described as a dodecahedron with pyritohedral symmetry; Dana J. et al., (1944), System of mineralogy, New York, p 282
↑ Mindat – bravoite. Mindat.org (2011-05-18). Retrieved on 2011-05-25.
↑ Pyrite on. Minerals.net (2011-02-23). Retrieved on 2011-05-25.
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Bowles, Oliver (1918) The structural and ornamental stones of Minnesota. Bulletin 663, United States Geological Survey, Washington. p. 25.
↑ Script error: No such module "Citation/CS1".
↑ Angelo, William (28 January 2009) A material odor mystery over foul-smelling drywall. Engineering News-Record.
↑ "Pyrite and your house, what home-owners should know Template:Webarchive" – Template:ISBN – Legal deposit – National Library of Canada, May 2000
↑ Shrimer, F. and Bromley, AV (2012) "Pyritic Heave in Ireland". Proceedings of the Euroseminar on Building Materials. International Cement Microscopy Association (Halle Germany)
↑ Homeowners in protest over pyrite damage to houses. The Irish Times (11 June 2011
↑ Brennan, Michael (22 February 2010) Devastating 'pyrite epidemic' hits 20,000 newly built houses. Irish Independent
↑ I.S. EN 13242:2002 Aggregates for unbound and hydraulically bound materials for use in civil engineering work and road construction Template:Webarchive
↑ ^a ^b Cite error: Invalid <ref> tag; no text was provided for refs named Hurlbut
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".

[1] Script error: No such module "citation/CS1".

[2] Script error: No such module "citation/CS1".

[3] Script error: No such module "citation/CS1".

[4] Script error: No such module "citation/CS1".

[5] Template:LSJ.

[6] Template:LSJ.

[7] Script error: No such module "citation/CS1".

[8] Template:Cite magazine

[9] Script error: No such module "citation/CS1".

[10] Script error: No such module "Citation/CS1".

[11] Script error: No such module "citation/CS1".

[12] Script error: No such module "citation/CS1".

[13] Script error: No such module "Citation/CS1".

[14] Script error: No such module "citation/CS1".

[15] Script error: No such module "citation/CS1".

[16] Script error: No such module "Citation/CS1".

[auto-17] Script error: No such module "Citation/CS1".

[18] Script error: No such module "citation/CS1".

[19] Script error: No such module "citation/CS1".

[20] Script error: No such module "Citation/CS1".

[21] Script error: No such module "citation/CS1".

[22] Script error: No such module "citation/CS1".

[23] Script error: No such module "Citation/CS1".

[24] Script error: No such module "citation/CS1".

[25] Script error: No such module "citation/CS1".

[26] Script error: No such module "Citation/CS1".

[27] Script error: No such module "Citation/CS1".

[28] Script error: No such module "Citation/CS1".

[Vaughan-29] Script error: No such module "citation/CS1".

[Brag1913-30] Script error: No such module "Citation/CS1".

[Birk1991-31] Script error: No such module "Citation/CS1".

[Bres1994-32] Script error: No such module "Citation/CS1".

[33] Script error: No such module "Citation/CS1".

[34] Script error: No such module "Citation/CS1".

[BJPC1992-35] Script error: No such module "Citation/CS1".

[36] Script error: No such module "Citation/CS1".

[Bonev2005-37] Script error: No such module "Citation/CS1".

[38] The pyritohedral form is described as a dodecahedron with pyritohedral symmetry; Dana J. et al., (1944), System of mineralogy, New York, p 282

[39] Mindat – bravoite. Mindat.org (2011-05-18). Retrieved on 2011-05-25.

[40] Pyrite on. Minerals.net (2011-02-23). Retrieved on 2011-05-25.

[41] Script error: No such module "citation/CS1".

[42] Script error: No such module "Citation/CS1".

[43] Script error: No such module "Citation/CS1".

[44] Script error: No such module "Citation/CS1".

[45] Bowles, Oliver (1918) The structural and ornamental stones of Minnesota. Bulletin 663, United States Geological Survey, Washington. p. 25.

[46] Script error: No such module "Citation/CS1".

[47] Angelo, William (28 January 2009) A material odor mystery over foul-smelling drywall. Engineering News-Record.

[48] "Pyrite and your house, what home-owners should know Template:Webarchive" – Template:ISBN – Legal deposit – National Library of Canada, May 2000

[49] Shrimer, F. and Bromley, AV (2012) "Pyritic Heave in Ireland". Proceedings of the Euroseminar on Building Materials. International Cement Microscopy Association (Halle Germany)

[50] Homeowners in protest over pyrite damage to houses. The Irish Times (11 June 2011

[51] Brennan, Michael (22 February 2010) Devastating 'pyrite epidemic' hits 20,000 newly built houses. Irish Independent

[52] I.S. EN 13242:2002 Aggregates for unbound and hydraulically bound materials for use in civil engineering work and road construction Template:Webarchive

[Hurlbut-53] Cite error: Invalid <ref> tag; no text was provided for refs named Hurlbut

[54] Script error: No such module "Citation/CS1".

[55] Script error: No such module "citation/CS1".

[56] Script error: No such module "Citation/CS1".

[57] Script error: No such module "citation/CS1".

[58] Script error: No such module "citation/CS1".

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]

[12]

[13]

[14]

[15]

[16]

[17]

[18]

[19]

[20]

[21]

[22]

[23]

[24]

[25]

[26]

[27]

[28]

[29]

[30]

[31]

[32]

[33]

[34]

[35]

[36]

[37]

[38]

[39]

[40]

[41]

[42]

[43]

[44]

[45]

[46]

[47]

[48]

[49]

[50]

[51]

[52]

[53]

[54]

[55]

[56]

[57]

[58]

@@ Line 1: / Line 1: @@
 {{Short description|Iron (II) disulfide mineral}}
-{{distinguish|Gold}}
 {{Redirect|Fool's Gold}}
 {{About|iron pyrite|other pyrite minerals|Pyrite group}}
@@ Line 40: / Line 39: @@
 | solubility  = Insoluble in water
 | diaphaneity = Opaque
-| other       = [[diamagnetism|Diamagnetic]] to [[paramagnetism|paramagnetic]] <br> A semiconductor with bandgap of 0.72 to 3.26 eV.
+| other       = [[diamagnetism|Diamagnetic]] to [[paramagnetism|paramagnetic]] <br /> A semiconductor with bandgap of 0.72 to 3.26 eV.
-| references  =<ref name=Hurlbut>{{cite book |author1=Hurlbut, Cornelius S. |author2=Klein, Cornelis |year=1985 |title=Manual of Mineralogy |edition=20th |publisher=John Wiley and Sons |location=New York, NY |pages=[https://archive.org/details/manualofmineralo00klei/page/285 285–286] |isbn=978-0-471-80580-9 |url-access=registration |url=https://archive.org/details/manualofmineralo00klei/page/285 }}</ref><ref>{{cite web |url=http://webmineral.com/data/Pyrite.shtml |title=Pyrite |website=Webmineral.com |access-date=2011-05-25}}</ref><ref>{{cite web |url=http://www.mindat.org/min-3314.html |title=Pyrite |website=Mindat.org |access-date=2011-05-25}}</ref><ref>{{cite book|editor=Anthony, John W. |editor2=Bideaux, Richard A. |editor3=Bladh, Kenneth W. |editor4=Nichols, Monte C. |title= Handbook of Mineralogy|publisher= Mineralogical Society of America|place= Chantilly, Virginia, US|chapter-url=http://rruff.geo.arizona.edu/doclib/hom/pyrite.pdf|chapter=Pyrite |isbn=978-0962209734 |volume=I (Elements, Sulfides, Sulfosalts)|year=1990}}</ref>
+| references  =<ref name=Hurlbut>{{cite book |author1=Hurlbut, Cornelius S. |author2=Klein, Cornelis |year=1985 |title=Manual of Mineralogy |edition=20th |publisher=John Wiley and Sons |location=New York, NY |pages=[https://archive.org/details/manualofmineralo00klei/page/285 285–286] |isbn=978-0-471-80580-9 |url-access=registration |url=https://archive.org/details/manualofmineralo00klei/page/285 }}</ref><ref>{{cite web |url=http://webmineral.com/data/Pyrite.shtml |title=Pyrite |website=Webmineral.com |access-date=2011-05-25}}</ref><ref>{{cite web |url=http://www.mindat.org/min-3314.html |title=Pyrite |website=Mindat.org |access-date=2011-05-25}}</ref><ref>{{cite book|editor=Anthony, John W. |editor2=Bideaux, Richard A. |editor3=Bladh, Kenneth W. |editor4=Nichols, Monte C. |title= Handbook of Mineralogy|publisher= Mineralogical Society of America|place= Chantilly, Virginia, US|chapter-url=http://rruff.geo.arizona.edu/doclib/hom/pyrite.pdf|chapter=Pyrite |isbn=978-0-9622097-3-4 |volume=I (Elements, Sulfides, Sulfosalts)|year=1990}}</ref>
 }}
 The [[mineral]] '''pyrite''' ({{IPAc-en|ˈ|p|aɪ|r|aɪ|t}} {{respell|PY|ryte}}),<ref>{{Cite web|url=https://dictionary.cambridge.org/dictionary/english/pyrite|title=Pyrite &#124; meaning in the Cambridge English Dictionary|website=dictionary.cambridge.org}}</ref> or '''iron pyrite''', also known as '''fool's gold''', is an [[iron sulfide]] with the [[chemical formula]] [[Iron|Fe]][[Sulfur|S]]<sub>2</sub> (iron (II) disulfide).<!-- Per section on oxidation states, iron (II) is correct. The sulfur is present as persulfide ion.--> Pyrite is the most abundant [[sulfide mineral]].<ref>{{cite book |url=https://books.google.com/books?id=0mXxAAAAMAAJ&pg=PA137 |page=137 |title=Sulfide Deposits in the Coosa Valley Area, Georgia |author1=Vernon J. Hurst |author2=Thomas J. Crawford |publisher=Economic Development Administration, Technical Assistance Project, U. S. Department of Commerce |year=1970}}</ref>
 [[File:2780M-pyrite1.jpg|thumb|Pyrite cubic crystals on [[marl]] from [[Navajún]], [[La Rioja (Spain)|La Rioja]], Spain (size: {{convert|95|by|78|mm|disp=sqbr}}, {{convert|512|g|disp=sqbr}}; main crystal: {{convert|31|mm|disp=sqbr}} on edge)]]
-Pyrite's metallic [[Lustre (mineralogy)|luster]] and pale brass-yellow [[hue]] give it a superficial resemblance to [[gold]], hence the well-known nickname of ''fool's gold''. The color has also led to the nicknames ''brass'', ''brazzle'', and ''brazil'', primarily used to refer to pyrite found in [[coal]].<ref>{{cite book |author1=Jackson, Julia A. |author2=Mehl, James |author3=Neuendorf, Klaus |url=https://books.google.com/books?id=SfnSesBc-RgC&pg=PA82 |via=Google Books |title=Glossary of Geology |publisher=American Geological Institute |year=2005 |page=82|isbn=9780922152766 }}</ref><ref>{{cite book |author=Fay, Albert H. |url=https://books.google.com/books?id=fB4bAAAAYAAJ&pg=PA103 |via=Google Books |title=A Glossary of the Mining and Mineral Industry |publisher=United States Bureau of Mines |year=1920 |pages=103–104}}</ref>
+Pyrite's metallic [[Lustre (mineralogy)|luster]] and pale brass-yellow [[hue]] give it a superficial resemblance to [[gold]], hence the well-known nickname of ''fool's gold''. The color has also led to the nicknames ''brass'', ''brazzle'', and ''brazil'', primarily used to refer to pyrite found in [[coal]].<ref>{{cite book |author1=Jackson, Julia A. |author2=Mehl, James |author3=Neuendorf, Klaus |url=https://books.google.com/books?id=SfnSesBc-RgC&pg=PA82 |via=Google Books |title=Glossary of Geology |publisher=American Geological Institute |year=2005 |page=82|isbn=978-0-922152-76-6 }}</ref><ref>{{cite book |author=Fay, Albert H. |url=https://books.google.com/books?id=fB4bAAAAYAAJ&pg=PA103 |via=Google Books |title=A Glossary of the Mining and Mineral Industry |publisher=United States Bureau of Mines |year=1920 |pages=103–104}}</ref>
 The name ''pyrite'' is derived from the [[Greek language|Greek]] {{lang|grc|πυρίτης λίθος}} ({{lang|grc-Latn|pyritēs lithos}}), 'stone or mineral which strikes fire',<ref>{{LSJ|puri/ths1|πυρίτης|ref}}.</ref> in turn from {{lang|grc|πῦρ}} ({{lang|grc-Latn|pŷr}}), 'fire'.<ref>{{LSJ|pu{{=}}r|πῦρ|shortref}}.</ref> In ancient Roman times, this name was applied to several types of stone that would create sparks when struck against [[steel]]; [[Pliny the Elder]] described one of them as being brassy, almost certainly a reference to what is now called pyrite.<ref>{{cite book |author1=Dana, James Dwight |author2=Dana, Edward Salisbury |url=https://books.google.com/books?id=lHS7AAAAIAAJ&pg=PA86 |title=Descriptive Mineralogy |edition=6th |publisher=Wiley |location=New York |year=1911 |page=86}}</ref>
-By [[Georgius Agricola]]'s time, {{circa|1550}}, the term had become a generic term for all of the [[pyrite group|sulfide minerals]].<ref>{{cite magazine |translator1=Hoover, H.C. |translator1-link=Herbert Clark Hoover |translator2=Hoover, L.H. |translator2-link=Lou Henry Hoover |title=De re metallica |magazine=The Mining Magazine |location=London |orig-year=1912 |publisher=Dover |year=1950 |at=see footnote on p 112|title-link=De re metallica }}</ref>
+By [[Georgius Agricola]]'s time, {{circa|1550}}, the term had become a generic term for all of the [[pyrite group|sulfide minerals]].<ref>{{cite magazine |translator1=Hoover, H.C. |translator1-link=Herbert Clark Hoover |translator2=Hoover, L.H. |translator2-link=Lou Henry Hoover |title=De re metallica |magazine=The Mining Magazine |location=London |orig-date=1912 |publisher=Dover |year=1950 |at=see footnote on p 112|title-link=De re metallica }}</ref>
 [[File:Pyrite under Normal and Polarized light.jpg|thumb|Pyrite under normal and polarized light]]
-Pyrite is usually found associated with other sulfides or [[oxide]]s in [[quartz]] [[Vein (geology)|veins]], [[sedimentary rock]], and [[metamorphic rock]], as well as in coal beds and as a replacement mineral in [[fossil]]s, but has also been identified in the [[sclerite]]s of [[Scaly-foot snail|scaly-foot gastropods]].<ref>{{cite news |url=http://news.nationalgeographic.com/news/2003/11/1107_031107_snailarmor.html |archive-url=https://web.archive.org/web/20031110015525/http://news.nationalgeographic.com/news/2003/11/1107_031107_snailarmor.html |url-status=dead |archive-date=November 10, 2003 |title=Armor-plated snail discovered in deep sea |website=news.nationalgeographic.com |access-date=2016-08-29 |publisher=National Geographic Society |location=Washington, DC}}</ref> Despite being nicknamed "fool's gold", pyrite is sometimes found in association with small quantities of gold. A substantial proportion of the gold is "[[Carlin–type gold deposit|invisible gold]]" incorporated into the pyrite. It has been suggested that the presence of both gold and [[arsenic]] is a case of [[coupled substitution]] but as of 1997 the chemical state of the gold remained controversial.<ref>{{cite journal |author1=Fleet, M. E. |author2=Mumin, A. Hamid |url=http://www.minsocam.org/msa/AmMin/toc/Articles_Free/1997/Fleet_p182-193_97.pdf |title=Gold-bearing arsenian pyrite and marcasite and arsenopyrite from Carlin Trend gold deposits and laboratory synthesis |journal=American Mineralogist |volume=82 |issue=1–2 |year=1997 |pages=182–193|doi=10.2138/am-1997-1-220 |bibcode=1997AmMin..82..182F |s2cid=55899431 }}</ref>
+Pyrite is usually found associated with other sulfides or [[oxide]]s in [[quartz]] [[Vein (geology)|veins]], [[sedimentary rock]], and [[metamorphic rock]], as well as in coal beds and as a replacement mineral in [[fossil]]s, but has also been identified in the [[sclerite]]s of [[Scaly-foot snail|scaly-foot gastropods]].<ref>{{cite news |url=http://news.nationalgeographic.com/news/2003/11/1107_031107_snailarmor.html |archive-url=https://web.archive.org/web/20031110015525/http://news.nationalgeographic.com/news/2003/11/1107_031107_snailarmor.html |archive-date=November 10, 2003 |title=Armor-plated snail discovered in deep sea |website=news.nationalgeographic.com |access-date=2016-08-29 |publisher=National Geographic Society |location=Washington, DC}}</ref> Despite being nicknamed "fool's gold", pyrite is sometimes found in association with small quantities of gold. A substantial proportion of the gold is "[[Carlin–type gold deposit|invisible gold]]" incorporated into the pyrite. It has been suggested that the presence of both gold and [[arsenic]] is a case of [[coupled substitution]] but as of 1997 the chemical state of the gold remained controversial.<ref>{{cite journal |author1=Fleet, M. E. |author2=Mumin, A. Hamid |url=http://www.minsocam.org/msa/AmMin/toc/Articles_Free/1997/Fleet_p182-193_97.pdf |title=Gold-bearing arsenian pyrite and marcasite and arsenopyrite from Carlin Trend gold deposits and laboratory synthesis |journal=American Mineralogist |volume=82 |issue=1–2 |year=1997 |pages=182–193|doi=10.2138/am-1997-1-220 |bibcode=1997AmMin..82..182F |s2cid=55899431 }}</ref>
 == Uses ==
@@ Line 60: / Line 59: @@
 Pyrite gained a brief popularity in the 16th and 17th&nbsp;centuries as a source of [[Combustion|ignition]] in early [[firearm]]s, most notably the [[wheellock]], where a sample of pyrite was placed against a circular file to strike the sparks needed to fire the gun.<ref>{{Cite book|last=Larson|first=Bruce|date=2003|title=An Interpretation of Firearms in the Archaeological Record in Virginia 1607-1625|chapter=Firearms|chapter-url=https://link.gale.com/apps/doc/CX2831100051/GVRL?u=lond95336&sid=GVRL&xid=edf7e554|series=Dissertations, Theses, and Masters Projects|volume=1|pages=413–418}}</ref>
-Pyrite is used with [[flint]]stone and a form of [[tinder]] made of [[stringybark]] by the [[Kaurna people]] of [[South Australia]], as a traditional method of starting fires.<ref>{{cite web | last=Schultz | first=Chester | title=Place Name Summary 6/23: Brukangga and Tindale's uses of the word bruki | website=Adelaide Research & Scholarship | publisher=[[University of Adelaide]] | date=22 October 2018 | url=https://www.adelaide.edu.au/kwp/placenames/research-publ/6-23Brukangga.pdf | access-date=16 November 2020 | archive-date=10 September 2021 | archive-url=https://web.archive.org/web/20210910191311/https://www.adelaide.edu.au/kwp/placenames/research-publ/6-23Brukangga.pdf | url-status=dead }}</ref>
+Pyrite is used with [[flint]]stone and a form of [[tinder]] made of [[stringybark]] by the [[Kaurna people]] of [[South Australia]], as a traditional method of starting fires.<ref>{{cite web | last=Schultz | first=Chester | title=Place Name Summary 6/23: Brukangga and Tindale's uses of the word bruki | website=Adelaide Research & Scholarship | publisher=[[University of Adelaide]] | date=22 October 2018 | url=https://www.adelaide.edu.au/kwp/placenames/research-publ/6-23Brukangga.pdf | access-date=16 November 2020 | archive-date=10 September 2021 | archive-url=https://web.archive.org/web/20210910191311/https://www.adelaide.edu.au/kwp/placenames/research-publ/6-23Brukangga.pdf }}</ref>
 Pyrite has been used since classical times to manufacture ''copperas'' ([[Iron(II) sulfate|ferrous sulfate]]). Iron pyrite was heaped up and allowed to weather (an example of an early form of [[heap leaching]]). The acidic runoff from the heap was then boiled with iron to produce iron sulfate. In the 15th century, new methods of such leaching began to replace the burning of sulfur as a source of [[sulfuric acid]]. By the 19th&nbsp;century, it had become the dominant method.<ref>{{cite journal |title=Industrial England in the Middle of the Eighteenth Century |journal=Nature |volume=83 |issue=2113 |date=1910-04-28 |pages=264–268 |doi=10.1038/083264a0|bibcode = 1910Natur..83..264. |hdl=2027/coo1.ark:/13960/t63497b2h |s2cid=34019869 |url=https://archive.org/details/industrialenglan00woodrich |hdl-access=free }}</ref>
@@ Line 66: / Line 65: @@
 Pyrite remains in commercial use for the production of [[sulfur dioxide]], for use in such applications as the [[Pulp and paper industry|paper industry]], and in the manufacture of sulfuric acid. Thermal decomposition of pyrite into FeS ([[iron(II) sulfide]]) and elemental sulfur starts at {{cvt|540|C|||}}; at around {{cvt|700|C|||}}, ''p''<sub>S<sub>2</sub></sub> is about {{nowrap|1 atm}}.<ref>{{cite book |title=Principles of extractive metallurgy |author=Rosenqvist, Terkel |edition=2nd |publisher=Tapir Academic Press |year=2004 |isbn=978-82-519-1922-7 |page=52 |url=https://books.google.com/books?id=I2mg2ine4AEC&pg=PA52 }}</ref>
-A newer commercial use for pyrite is as the [[cathode]] material in [[Energizer]] brand non-rechargeable [[Lithium metal battery|lithium metal batteries]].<ref>{{cite book |publisher=Energizer Corporation |url=http://data.energizer.com/PDFs/lithiuml91l92_appman.pdf |title=Lithium-Iron Disulfide (Li-FeS<sub>2</sub>) |series=Handbook and Application Manual |date=2017-09-19 |article=Cylindrical Primary Lithium [battery] |access-date=2018-04-20 |archive-date=2006-03-17 |archive-url=https://web.archive.org/web/20060317180835/http://data.energizer.com/PDFs/lithiuml91l92_appman.pdf |url-status=dead }}</ref>
+A newer commercial use for pyrite is as the [[cathode]] material in [[Energizer]] brand non-rechargeable [[Lithium metal battery|lithium metal batteries]].<ref>{{cite book |publisher=Energizer Corporation |url=http://data.energizer.com/PDFs/lithiuml91l92_appman.pdf |title=Lithium-Iron Disulfide (Li-FeS<sub>2</sub>) |series=Handbook and Application Manual |date=2017-09-19 |article=Cylindrical Primary Lithium [battery] |access-date=2018-04-20 |archive-date=2006-03-17 |archive-url=https://web.archive.org/web/20060317180835/http://data.energizer.com/PDFs/lithiuml91l92_appman.pdf }}</ref>
-Pyrite is a [[semiconductor material]] with a [[band gap]] of 0.95 [[Electronvolt|eV]].<ref>{{cite journal |url=http://www.esqsec.unibe.ch/%5Cpub%5Cpub_51.htm |title=Iron Disulfide (Pyrite) as Photovoltaic Material: Problems and Opportunities |author1=Ellmer, K. |author2=Tributsch, H. |name-list-style=amp |journal=Proceedings of the 12th Workshop on Quantum Solar Energy Conversion – (QUANTSOL 2000) |date=2000-03-11 |url-status=dead |archive-url=https://web.archive.org/web/20100115000025/http://www.esqsec.unibe.ch/pub/pub_51.htm |archive-date=2010-01-15 }}</ref> Pure pyrite is naturally n-type, in both crystal and thin-film forms, potentially due to sulfur vacancies in the pyrite crystal structure acting as n-dopants.<ref name="auto">{{cite journal |title=Potential resolution to the doping puzzle in iron pyrite: Carrier type determination by Hall effect and thermopower |author1=Xin Zhang |author2=Mengquin Li |name-list-style=amp |journal=Physical Review Materials |volume=1 |date=2017-06-19 |issue=1 |page=015402 |doi=10.1103/PhysRevMaterials.1.015402 |bibcode=2017PhRvM...1a5402Z |doi-access=free }}</ref>
+Pyrite is a [[semiconductor material]] with a [[band gap]] of 0.95 [[Electronvolt|eV]].<ref>{{cite journal |url=http://www.esqsec.unibe.ch/%5Cpub%5Cpub_51.htm |title=Iron Disulfide (Pyrite) as Photovoltaic Material: Problems and Opportunities |author1=Ellmer, K. |author2=Tributsch, H. |name-list-style=amp |journal=Proceedings of the 12th Workshop on Quantum Solar Energy Conversion – (QUANTSOL 2000) |date=2000-03-11 |archive-url=https://web.archive.org/web/20100115000025/http://www.esqsec.unibe.ch/pub/pub_51.htm |archive-date=2010-01-15 }}</ref> Pure pyrite is naturally [[Extrinsic_semiconductor#N-type_semiconductors|n-type]], in both crystal and thin-film forms, potentially due to sulfur vacancies in the pyrite crystal structure acting as n-dopants.<ref name="auto">{{cite journal |title=Potential resolution to the doping puzzle in iron pyrite: Carrier type determination by Hall effect and thermopower |author1=Xin Zhang |author2=Mengquin Li |name-list-style=amp |journal=Physical Review Materials |volume=1 |date=2017-06-19 |issue=1 |article-number=015402 |doi=10.1103/PhysRevMaterials.1.015402 |bibcode=2017PhRvM...1a5402Z |doi-access=free }}</ref>
-During the early years of the 20th&nbsp;century, pyrite was used as a [[Cat's-whisker detector|mineral detector]] in [[radio]] receivers, and is still used by [[crystal radio]] hobbyists. Until the [[vacuum tube]] matured, the crystal detector was the most sensitive and dependable [[detector (radio)|detector]] available—with considerable variation between mineral types and even individual samples within a particular type of mineral. Pyrite detectors occupied a midway point between [[galena]] detectors and the more mechanically complicated [[Cat's-whisker detector#Types|perikon]] mineral pairs. Pyrite detectors can be as sensitive as a modern 1N34A [[germanium]] [[diode]] detector.<ref>{{cite book |url=https://books.google.com/books?id=eSguAAAAYAAJ&pg=PA302 |title=The Principles Underlying Radio Communication |series=Radio Pamphlet |volume=40 |department=U.S. Army Signal Corps |date=1918 |at=section&nbsp;179, pp 302–305 |via=Google Books}}</ref><ref>{{cite book |author=Thomas H. Lee |url=https://books.google.com/books?id=DzcMK-2mFQUC&pg=PA4 |title=The Design of Radio Frequency Integrated Circuits |edition=2nd |publisher=Cambridge University Press |location=Cambridge, UK |year=2004 |pages=4–6 |via=Google Books|isbn=9780521835398 }}</ref>
+During the early years of the 20th&nbsp;century, pyrite was used as a [[Cat's-whisker detector|mineral detector]] in [[radio]] receivers, and is still used by [[crystal radio]] hobbyists. Until the [[vacuum tube]] matured, the crystal detector was the most sensitive and dependable [[detector (radio)|detector]] available—with considerable variation between mineral types and even individual samples within a particular type of mineral. Pyrite detectors occupied a midway point between [[galena]] detectors and the more mechanically complicated [[Cat's-whisker detector#Types|perikon]] mineral pairs. Pyrite detectors can be as sensitive as a modern 1N34A [[germanium]] [[diode]] detector.<ref>{{cite book |url=https://books.google.com/books?id=eSguAAAAYAAJ&pg=PA302 |title=The Principles Underlying Radio Communication |series=Radio Pamphlet |volume=40 |department=U.S. Army Signal Corps |date=1918 |at=section&nbsp;179, pp 302–305 |via=Google Books}}</ref><ref>{{cite book |author=Thomas H. Lee |url=https://books.google.com/books?id=DzcMK-2mFQUC&pg=PA4 |title=The Design of Radio Frequency Integrated Circuits |edition=2nd |publisher=Cambridge University Press |location=Cambridge, UK |year=2004 |pages=4–6 |via=Google Books|isbn=978-0-521-83539-8 }}</ref>
 Pyrite has been proposed as an abundant, non-toxic, inexpensive material in low-cost [[photovoltaic]] solar panels.<ref>{{cite journal |title=Materials availability expands the opportunity for large-scale photovoltaics deployment |year=2009 |last1=Wadia |first1=Cyrus |last2=Alivisatos |first2=A. Paul |last3=Kammen |first3=Daniel M. |journal=Environmental Science & Technology |volume=43 |issue=6 |pages=2072–7 |doi=10.1021/es8019534 |bibcode=2009EnST...43.2072W |pmid=19368216|s2cid=36725835 }}</ref> Synthetic iron sulfide was used with [[copper sulfide]] to create the photovoltaic material.<ref>{{cite news |url=http://www.berkeley.edu/news/media/releases/2009/02/17_solar.shtml |title=Cheaper materials could be key to low-cost solar cells |publisher=University of California – Berkeley |location=Berkeley, CA |author=Sanders, Robert |date=17 February 2009}}</ref> More recent efforts are working toward thin-film solar cells made entirely of pyrite.<ref name="auto"/>
@@ Line 79: / Line 78: @@
 ==Research==
-In July 2020 scientists reported that they have observed a voltage-induced transformation of normally [[diamagnetic]] pyrite into a [[ferromagnetic]] material, which may lead to applications in devices such as solar cells or magnetic data storage.<ref>{{cite news |title='Fool's gold' may be valuable after all |url=https://phys.org/news/2020-07-gold-valuable.html |access-date=17 August 2020 |work=phys.org |language=en}}</ref><ref>{{cite journal |last1=Walter |first1=Jeff |last2=Voigt |first2=Bryan |last3=Day-Roberts |first3=Ezra |last4=Heltemes |first4=Kei |last5=Fernandes |first5=Rafael M. |last6=Birol |first6=Turan |last7=Leighton |first7=Chris |title=Voltage-induced ferromagnetism in a diamagnet |journal=Science Advances |date=1 July 2020 |volume=6 |issue=31 |pages=eabb7721 |doi=10.1126/sciadv.abb7721 |pmid=32832693 |pmc=7439324 |bibcode=2020SciA....6.7721W |language=en |issn=2375-2548|doi-access=free }}</ref>
+In July 2020 scientists reported that they have observed a voltage-induced transformation of normally [[diamagnetic]] pyrite into a [[ferromagnetic]] material, which may lead to applications in devices such as solar cells or magnetic data storage.<ref>{{cite news |title='Fool's gold' may be valuable after all |url=https://phys.org/news/2020-07-gold-valuable.html |access-date=17 August 2020 |work=phys.org |language=en}}</ref><ref>{{cite journal |last1=Walter |first1=Jeff |last2=Voigt |first2=Bryan |last3=Day-Roberts |first3=Ezra |last4=Heltemes |first4=Kei |last5=Fernandes |first5=Rafael M. |last6=Birol |first6=Turan |last7=Leighton |first7=Chris |title=Voltage-induced ferromagnetism in a diamagnet |journal=Science Advances |date=1 July 2020 |volume=6 |issue=31 |article-number=eabb7721 |doi=10.1126/sciadv.abb7721 |pmid=32832693 |pmc=7439324 |bibcode=2020SciA....6.7721W |language=en |issn=2375-2548|doi-access=free }}</ref>
 Researchers at [[Trinity College Dublin]], Ireland have demonstrated that FeS<sub>2</sub> can be exfoliated into few-layers just like other two-dimensional layered materials such as graphene by a simple liquid-phase exfoliation route. This is the first study to demonstrate the production of non-layered 2D-platelets from 3D bulk FeS<sub>2</sub>. Furthermore, they have used these 2D-platelets with 20% single walled carbon-nanotube as an anode material in lithium-ion batteries, reaching a capacity of 1000 mAh/g close to the theoretical capacity of FeS<sub>2</sub>.<ref>{{cite journal |last1=Kaur |first1=Harneet |last2=Tian |first2=Ruiyuan |last3=Roy |first3=Ahin |last4=McCrystall |first4=Mark |last5=Horváth |first5=Dominik V. |last6=Onrubia |first6=Guillermo L. |last7=Smith |first7=Ross |last8=Ruether |first8=Manuel |last9=Griffin |first9=Aideen |last10=Backes |first10=Claudia |last11=Nicolosi |first11=Valeria |last12=Coleman |first12=Jonathan N. |title=Production of Quasi-2D Platelets of Non-Layered Iron Pyrite (FeS<sub>2</sub>) by Liquid-Phase Exfoliation for High Performance Battery Electrodes |journal=ACS Nano |date=22 September 2020 |volume=14 |issue=10 |pages=13418–13432 |doi=10.1021/acsnano.0c05292 |pmid=32960568 |url=https://pubs.acs.org/doi/10.1021/acsnano.0c05292|hdl=2262/93605 |s2cid=221864018 |hdl-access=free }}</ref>
@@ Line 92: / Line 91: @@
 [[Image:FeS2structure.png|thumb|right|Crystal structure of pyrite. In the center of the cell a S<sub>2</sub><sup>2−</sup> pair is seen in yellow.]]
-Iron-pyrite FeS<sub>2</sub> represents the prototype compound of the [[Crystallography|crystallographic]] pyrite structure. The structure is [[cubic crystal system|cubic]] and was among the first [[crystal structures]] solved by [[X-ray diffraction]].<ref name=Brag1913>{{cite journal|author=Bragg, W. L.|title=The structure of some crystals as indicated by their diffraction of X-rays|journal=[[Proceedings of the Royal Society A]]|volume=89|pages=248–277|year=1913|doi=10.1098/rspa.1913.0083|bibcode=1913RSPSA..89..248B|issue=610|jstor=93488|doi-access=free}}</ref> It belongs to the crystallographic [[space group]] ''Pa''{{overline|3}} and is denoted by the [[Zeitschrift für Kristallographie|Strukturbericht]] notation C2. Under thermodynamic standard conditions the [[lattice constant]] <math>a</math> of stoichiometric iron pyrite FeS<sub>2</sub> amounts to {{nowrap|541.87 pm}}.<ref name=Birk1991>{{cite journal|title=Sulfur deficiency in iron pyrite (FeS<sub>2−x</sub>) and its consequences for band structure models|journal=Physical Review B|volume=43|pages=11926–11936|year=1991|doi=10.1103/PhysRevB.43.11926|bibcode=1991PhRvB..4311926B|issue=14|last1=Birkholz|first1=M.|last2=Fiechter|first2=S.|last3=Hartmann|first3=A.|last4=Tributsch|first4=H.|pmid=9996968}}</ref> The [[cubic crystal system#Voids in the unit cell|unit cell]] is composed of a Fe [[Bravais lattice|face-centered cubic sublattice]] into which the {{chem|S|2}} ions are embedded. (Note though that the iron atoms in the faces are not equivalent by translation alone to the iron atoms at the corners.) The pyrite structure is also seen in other ''MX''<sub>2</sub> compounds of [[transition metals]] ''M'' and [[chalcogen]]s ''X'' = [[oxygen|O]], [[sulfur|S]], [[selenium|Se]] and [[tellurium|Te]]. Certain [[pnictide|dipnictides]] with ''X'' standing for [[phosphorus|P]], [[arsenic|As]] and [[antimony|Sb]] etc. are also known to adopt the pyrite structure.<ref name=Bres1994>{{cite journal|title=Bonding Trends in Pyrites and a Reinvestigation of the Structure of PdAs<sub>2</sub>, PdSb<sub>2</sub>, PtSb<sub>2</sub> and PtBi<sub>2</sub>|journal=Z. Anorg. Allg. Chem.|volume=620|issue=3|pages=393–404|year=1994|doi=10.1002/zaac.19946200302|last1=Brese|first1=Nathaniel E.|last2=von Schnering|first2=Hans Georg}}</ref>
+Iron-pyrite FeS<sub>2</sub> represents the prototype compound of the [[Crystallography|crystallographic]] pyrite structure. The structure is [[cubic crystal system|cubic]] and was among the first [[crystal structures]] solved by [[X-ray diffraction]].<ref name=Brag1913>{{cite journal|author=Bragg, W. L.|title=The structure of some crystals as indicated by their diffraction of X-rays|journal=[[Proceedings of the Royal Society A]]|volume=89|pages=248–277|year=1913|doi=10.1098/rspa.1913.0083|bibcode=1913RSPSA..89..248B|issue=610|jstor=93488|doi-access=free}}</ref> It belongs to the crystallographic [[space group]] ''Pa''{{overline|3}} and is denoted by the [[Zeitschrift für Kristallographie|Strukturbericht]] notation C2. Under thermodynamic standard conditions the [[lattice constant]] <math>a</math> of stoichiometric iron pyrite FeS<sub>2</sub> amounts to {{nowrap|541.87 pm}}.<ref name=Birk1991>{{cite journal|title=Sulfur deficiency in iron pyrite (FeS<sub>2−x</sub>) and its consequences for band structure models|journal=Physical Review B|volume=43|pages=11926–11936|year=1991|doi=10.1103/PhysRevB.43.11926|bibcode=1991PhRvB..4311926B|issue=14|last1=Birkholz|first1=M.|last2=Fiechter|first2=S.|last3=Hartmann|first3=A.|last4=Tributsch|first4=H.|pmid=9996968}}</ref> The [[cubic crystal system#Voids in the unit cell|unit cell]] is composed of a Fe [[Bravais lattice|face-centered cubic sublattice]] into which the {{chem|S|2}} ions are embedded. (Note though that the iron atoms in the faces are not equivalent by translation alone to the iron atoms at the corners.) The pyrite structure is also seen in other ''MX''<sub>2</sub> compounds of [[transition metals]] ''M'' and [[chalcogen]]s ''X'' = [[oxygen|O]], [[sulfur|S]], [[selenium|Se]] and [[tellurium|Te]]. Certain [[pnictide|dipnictides]] with ''X'' standing for [[phosphorus|P]], [[arsenic|As]] and [[antimony|Sb]] etc. are also known to adopt the pyrite structure.<ref name=Bres1994>{{cite journal|title=Bonding Trends in Pyrites and a Reinvestigation of the Structure of PdAs<sub>2</sub>, PdSb<sub>2</sub>, PtSb<sub>2</sub> and PtBi<sub>2</sub>|journal=Z. Anorg. Allg. Chem.|volume=620|issue=3|pages=393–404|year=1994|doi=10.1002/zaac.19946200302|last1=Brese|first1=Nathaniel E.|last2=von Schnering|first2=Hans Georg |bibcode=1994ZAACh.620..393B }}</ref>
 The Fe atoms are bonded to six S atoms, giving a distorted octahedron. The material is a [[semiconductor]]. The Fe ions are usually considered to be ''[[low spin]]'' [[divalent]] state (as shown by [[Mössbauer spectroscopy]] as well as XPS). The material as a whole behaves as a Van Vleck [[Paramagnetism|paramagnet]], despite its low-spin divalency.<ref>{{Cite journal|last1=Burgardt|first1=P.|last2=Seehra|first2=M. S.|date=1977-04-01|title=Magnetic susceptibility of iron pyrite (FeS2) between 4.2 and 620 K|journal=Solid State Communications|volume=22|issue=2|pages=153–156|doi=10.1016/0038-1098(77)90422-7|bibcode=1977SSCom..22..153B|issn=0038-1098}}</ref>
-The sulfur centers occur in pairs, described as S<sub>2</sub><sup>2−</sup>.<ref>{{cite journal|last1=Hulliger|first1=F.|title=Electrical Properties of Pyrite-Type and Related Compounds with Zero Spin Moment|journal=Nature|date=December 1963|volume=200|issue=4911|pages=1064–1065|doi=10.1038/2001064a0|bibcode=1963Natur.200.1064H|s2cid=32504249}}</ref><!-- Really need a more recent source--> Reduction of pyrite with potassium gives [[potassium dithioferrate]], KFeS<sub>2</sub>. This material features ferric ions and isolated sulfide (S<sup>2−</sup>) centers.
+The sulfur centers occur in pairs, described as {{chem|S|2|2-}}.<ref>{{cite journal|last1=Hulliger|first1=F.|title=Electrical Properties of Pyrite-Type and Related Compounds with Zero Spin Moment|journal=Nature|date=December 1963|volume=200|issue=4911|pages=1064–1065|doi=10.1038/2001064a0|bibcode=1963Natur.200.1064H|s2cid=32504249}}</ref><!-- Really need a more recent source--> Reduction of pyrite with potassium gives [[potassium dithioferrate]], KFeS<sub>2</sub>. This material features ferric ions and isolated sulfide (S<sup>2−</sup>) centers.
 The S atoms are tetrahedral, being bonded to three Fe centers and one other S atom. The site symmetry at Fe and S positions is accounted for by [[crystallographic point group|point symmetry groups]] ''C''<sub>3''i''</sub> and ''C''<sub>3</sub>, respectively. The missing [[centrosymmetry|center of inversion]] at S lattice sites has important consequences for the crystallographic and physical properties of iron pyrite. These consequences derive from the crystal electric field active at the sulfur lattice site, which causes a [[Chemical polarity|polarization]] of S ions in the pyrite lattice.<ref name=BJPC1992>{{cite journal|author=Birkholz, M.|url=https://www.researchgate.net/publication/231101585|title=The crystal energy of pyrite|journal=J. Phys.: Condens. Matter|volume=4|pages=6227–6240|year=1992|doi=10.1088/0953-8984/4/29/007|bibcode=1992JPCM....4.6227B|issue=29|s2cid = 250815717 }}</ref> The polarisation can be calculated on the basis of higher-order [[Madelung constant]]s and has to be included in the calculation of the [[lattice energy]] by using a generalised [[Born–Haber cycle]]. This reflects the fact that the covalent bond in the sulfur pair is inadequately accounted for by a strictly ionic treatment.<ref>{{cite journal|last1=Wood|first1=Robert|title=Madelung Constants for the Calcium Carbide and Pyrite Crystal Structures|journal=The Journal of Chemical Physics|date=August 1962|volume=37|issue=3|pages=598–600|doi=10.1063/1.1701381|bibcode=1962JChPh..37..598W }}</ref>
@@ Line 113: / Line 112: @@
 ==Distinguishing similar minerals==
-Pyrite is distinguishable from [[Gold#Occurrence|native gold]] by its hardness, brittleness and crystal form. Pyrite fractures are very [[Fracture (mineralogy)#Uneven fracture|uneven]], sometimes [[conchoidal fracture|conchoidal]] because it does not cleave along a preferential plane. Native [[gold nugget]]s, or glitters, do not break but deform in a [[ductility|ductile]] way. Pyrite is brittle, gold is malleable.
+Pyrite is distinguishable from [[Gold#Occurrence|native gold]] by its hardness, brittleness and crystal form. Pyrite fractures are very [[Fracture (mineralogy)#Uneven fracture|uneven]], sometimes [[conchoidal fracture|conchoidal]] because it does not cleave along a preferential plane. Native [[gold nugget]]s, or glitters, do not break but deform in a [[ductility|ductile]] way. Pyrite is brittle, gold is malleable. Natural gold tends to be [[Euhedral and anhedral|anhedral]] (irregularly shaped without well defined faces), whereas pyrite comes as either cubes or multifaceted crystals with well developed and sharp faces easy to recognise. Well crystallised pyrite crystals are [[euhedral]] (''i.e.'', with nice faces). Pyrite can often be distinguished by the striations which, in many cases, can be seen on its surface.
-Natural gold tends to be [[Euhedral and anhedral|anhedral]] (irregularly shaped without well defined faces), whereas pyrite comes as either cubes or multifaceted crystals with well developed and sharp faces easy to recognise. Well crystallised pyrite crystals are [[euhedral]] (''i.e.'', with nice faces). Pyrite can often be distinguished by the striations which, in many cases, can be seen on its surface. [[Chalcopyrite]] ({{Chem2|CuFeS2}}) is brighter yellow with a greenish hue when wet and is softer (3.5–4 on Mohs' scale).<ref>[http://www.minerals.net/mineral/sulfides/pyrite/pyrite.htm Pyrite on]. Minerals.net (2011-02-23). Retrieved on 2011-05-25.</ref> [[Arsenopyrite]] (FeAsS) is silver white and does not become more yellow when wet.
+[[Chalcopyrite]] ({{Chem2|CuFeS2}}) is brighter yellow with a greenish hue when wet and is softer (3.5–4 on Mohs' scale).<ref>[http://www.minerals.net/mineral/sulfides/pyrite/pyrite.htm Pyrite on]. Minerals.net (2011-02-23). Retrieved on 2011-05-25.</ref> [[Arsenopyrite]] (FeAsS) is silver white and does not become more yellow when wet.
 ==Hazards==
@@ Line 125: / Line 124: @@
 Pyrite oxidation by atmospheric {{O2}} in the presence of moisture ({{H2O}}) initially produces ferrous ions ({{chem|Fe|2+}}) and [[sulfuric acid]] which dissociates into [[sulfate]] ions and [[hydronium|protons]], leading to [[acid mine drainage]] (AMD). An example of acid rock drainage caused by pyrite is the [[2015 Gold King Mine waste water spill]].<ref>{{cite web| url = http://www.westech-inc.com/en-usa/industry-solutions/mineral-overview/acid-mine-drainage| title = Acid Mine Drainage}}</ref>
-:{{chem2 | 2 FeS2 (s) + 7 O2 (g) + 2 H2O (l) -> 2 Fe(2+) (aq) + 4 SO4(2-) (aq) + 4 H+ (aq) }}
+:{{chem2 | 2 FeS2(s) + 7 O2(g) + 2 H2O(l) -> 2 Fe(2+)(aq) + 4 SO4(2-)(aq) + 4 H+(aq) }}
 ===Dust explosions===
@@ Line 139: / Line 138: @@
 Pyrite is the most common of sulfide minerals and is widespread in igneous, metamorphic, and sedimentary rocks. It is a common accessory mineral in igneous rocks, where it also occasionally occurs as larger masses arising from an [[Miscibility|immiscible]] sulfide phase in the original magma. It is found in metamorphic rocks as a product of [[contact metamorphism]]. It also forms as a high-temperature [[hydrothermal mineralization|hydrothermal mineral]], though it occasionally forms at lower temperatures.<ref name="Hurlbut"/>
-Pyrite occurs both as a primary mineral, present in the original sediments, and as a secondary mineral, deposited during [[diagenesis]].<ref name="Hurlbut"/> Pyrite and [[marcasite]] commonly occur as replacement [[pseudomorph]]s after [[fossils]] in [[black shale]] and other [[sedimentary rocks]] formed under [[Redox|reducing]] environmental conditions.<ref>{{Cite journal|last1=Briggs|first1=D. E. G.|last2=Raiswell|first2=R.|last3=Bottrell|first3=S. H.|last4=Hatfield|first4=D.|last5=Bartels|first5=C.|date=1996-06-01|title=Controls on the pyritization of exceptionally preserved fossils; an analysis of the Lower Devonian Hunsrueck Slate of Germany|journal=American Journal of Science|language=en|volume=296|issue=6|pages=633–663|doi=10.2475/ajs.296.6.633|issn=0002-9599|bibcode=1996AmJS..296..633B}}</ref> Pyrite is common as an accessory mineral in shale, where it is formed by precipitation from anoxic seawater, and coal beds often contain significant pyrite.<ref>{{cite book |last1=Nesse |first1=William D. |title=Introduction to mineralogy |date=2000 |publisher=Oxford University Press |location=New York |isbn=9780195106916 |page=390}}</ref>
+Pyrite occurs both as a primary mineral, present in the original sediments, and as a secondary mineral, deposited during [[diagenesis]].<ref name="Hurlbut"/> Pyrite and [[marcasite]] commonly occur as replacement [[pseudomorph]]s after [[fossils]] in [[black shale]] and other [[sedimentary rocks]] formed under [[Redox|reducing]] environmental conditions.<ref>{{Cite journal|last1=Briggs|first1=D. E. G.|last2=Raiswell|first2=R.|last3=Bottrell|first3=S. H.|last4=Hatfield|first4=D.|last5=Bartels|first5=C.|date=1996-06-01|title=Controls on the pyritization of exceptionally preserved fossils; an analysis of the Lower Devonian Hunsrueck Slate of Germany|journal=American Journal of Science|language=en|volume=296|issue=6|pages=633–663|doi=10.2475/ajs.296.6.633|issn=0002-9599|bibcode=1996AmJS..296..633B}}</ref> Pyrite is common as an accessory mineral in shale, where it is formed by precipitation from anoxic seawater, and coal beds often contain significant pyrite.<ref>{{cite book |last1=Nesse |first1=William D. |title=Introduction to mineralogy |date=2000 |publisher=Oxford University Press |location=New York |isbn=978-0-19-510691-6 |page=390}}</ref>
 Notable deposits are found as lenticular masses in Virginia, U.S., and in smaller quantities in many other locations. Large deposits are mined at Rio Tinto in Spain and elsewhere in the Iberian Peninsula.<ref>{{Cite journal |last=J.M. Leistel, E. Marcoux, D. Thiéblemont, C. Quesada, A. Sánchez, G.R. Almodóvar, E. Pascualand R. Sáez |title=The volcanic-hosted massive sulphide deposits of the Iberian Pyrite Belt |journal=Mineralium Deposita |date=1997 |volume=33 |issue=1–2 |pages=2–30|doi=10.1007/s001260050130 |bibcode=1997MinDe..33....2L }}</ref>
 ==Cultural beliefs==
-In the beliefs of the Thai people (especially those in the south), pyrite is known as ''Khao tok [[Phra Ruang]]'', ''Khao khon bat Phra Ruang'' (ข้าวตอกพระร่วง, ข้าวก้นบาตรพระร่วง) or ''Phet na tang'', ''Hin na tang'' (เพชรหน้าทั่ง, หินหน้าทั่ง). It is believed to be a [[amulet|sacred item]] that has the power to prevent evil, [[black magic]] or demons.<ref>{{cite web|url=https://www.dailynews.co.th/regional/736100/|title=ไขข้อข้องใจ'เพชรหน้าทั่ง' สรรพคุณรองจาก'เหล็กไหล'|date=2019-10-11|accessdate=2021-08-26|work=Daily News|language=thai|trans-title=Solve the question of 'Phet na tang', secondary properties after 'Lek Lai'}}</ref><ref>{{cite web|url=https://www.komchadluek.net/news/local/458649|work=Komchadluek|language=Thai|date=2021-02-17|accessdate=2021-08-26|title=ของดีหายาก "ข้าวตอกพระร่วง-ข้าวก้นบาตรพระร่วง" หินศักดิ์สิทธิ์แห่งกรุงสุโขทัย|trans-title=A rare good item "Khao tok Phra Ruang - Khao khon bat Phra Ruang", a sacred stone of Sukhothai kingdom}}</ref>
+In the beliefs of the Thai people (especially those in the south), pyrite is known as ''Khao tok [[Phra Ruang]]'', ''Khao khon bat Phra Ruang'' (ข้าวตอกพระร่วง, ข้าวก้นบาตรพระร่วง) or ''Phet na tang'', ''Hin na tang'' (เพชรหน้าทั่ง, หินหน้าทั่ง){{Clarify|reason=What do these Thai phrases translate to?|date=November 2025}}. It is believed to be a [[amulet|sacred item]] that has the power to prevent evil, [[black magic]] or demons.<ref>{{cite web|url=https://www.dailynews.co.th/regional/736100/|title=ไขข้อข้องใจ'เพชรหน้าทั่ง' สรรพคุณรองจาก'เหล็กไหล'|date=2019-10-11|access-date=2021-08-26|work=Daily News|language=thai|trans-title=Solve the question of 'Phet na tang', secondary properties after 'Lek Lai'}}</ref><ref>{{cite web|url=https://www.komchadluek.net/news/local/458649|work=Komchadluek|language=Thai|date=2021-02-17|access-date=2021-08-26|title=ของดีหายาก "ข้าวตอกพระร่วง-ข้าวก้นบาตรพระร่วง" หินศักดิ์สิทธิ์แห่งกรุงสุโขทัย|trans-title=A rare good item "Khao tok Phra Ruang - Khao khon bat Phra Ruang", a sacred stone of Sukhothai kingdom}}</ref>
-==Images==
+==Gallery==
 <gallery widths="133px" heights="130px">
-File:Bullypyrite2.jpg|As a [[Fossil#Replacement and recrystallization|replacement mineral]] in an [[ammonite]] from France
+File:Bullypyrite2.jpg|Pyrite as a [[Fossil#Replacement and recrystallization|replacement mineral]] in an [[ammonite]] from France
 File:Pyrite from Ampliación a Victoria Mine, Navajún, La Rioja, Spain 2.jpg|Pyrite from Ampliación a Victoria Mine, Navajún, La Rioja, Spain
 File:Pyrite-Tetrahedrite-Quartz-184642.jpg|Pyrite from the [[Sweet Home Mine]], with golden striated cubes intergrown with minor tetrahedrite, on a bed of transparent quartz needles
 File:Pyrite-200582.jpg|Radiating form of pyrite
 File:Paraspirifer bownockeri.fond.jpg|''[[Paraspirifer|Paraspirifer bownockeri]]'' in pyrite
-File:Fluorite-Pyrite-tmu38b.jpg|Pink fluorite perched between pyrite on one side and metallic galena on the other side
+File:Fluorite-Pyrite-tmu38b.jpg|Pink fluorite perched between pyrite (left) and metallic galena (right)
-File:Pyrite in pyrrhotite SEM image.png|SEM image of intergrowth of pyrite cuboctahedral crystals (yellow) and pyrrhotite (pinkish yellow)
+File:Pyrite in pyrrhotite SEM image.png|[[Scanning electron microscope|SEM]] image of intergrowth of pyrite cuboctahedral crystals (yellow) and [[pyrrhotite]] (pinkish yellow)
 </gallery>

Pyrite: Difference between revisions

Latest revision as of 05:00, 15 November 2025

Contents

Uses

Research

Formal oxidation states for pyrite, marcasite, molybdenite and arsenopyrite

Crystallography

Crystal habit

Varieties

Distinguishing similar minerals

Hazards

Pyrite oxidation and acid mine drainage

Dust explosions

Weakened building materials

Occurrence

Cultural beliefs

Gallery

See also

References

Further reading

External links

Navigation menu

Pyrite: Difference between revisions

Latest revision as of 05:00, 15 November 2025

Uses

Research

Formal oxidation states for pyrite, marcasite, molybdenite and arsenopyrite

Crystallography

Crystal habit

Varieties

Distinguishing similar minerals

Hazards

Pyrite oxidation and acid mine drainage

Dust explosions

Weakened building materials

Occurrence

Cultural beliefs

Gallery

See also

References

Further reading

External links

Navigation menu

Search