View source for Silicate mineral

{{Short description|Rock-forming minerals with predominantly silicate anions}}
{{Use dmy dates|date=February 2019}}
[[File:Spodumene-sd305c.jpg|thumb|right|Lithium aluminium silicate mineral [[spodumene]]]]

'''Silicate minerals''' are rock-forming [[mineral]]s made up of [[silicate]] groups. They are the largest and most important class of minerals and make up approximately 90 percent of [[Earth's crust]].<ref>{{cite web|url=https://www.britannica.com/science/mineral-chemical-compound/Silicates|title=Mineral - Silicates|website=britannica.com|access-date=8 May 2018|url-status=live|archive-url=https://web.archive.org/web/20171025133427/https://www.britannica.com/science/mineral-chemical-compound/Silicates|archive-date=25 October 2017}}</ref><ref name=deer>{{Cite book| last = Deer| first = W.A.|author2=Howie, R.A.|author3=Zussman, J. | year = 1992| title = [[An introduction to the rock-forming minerals]]| publisher = Longman| location = London| edition = 2nd| isbn = 0-582-30094-0}}</ref><ref name=hurlbut>{{Cite book| last = Hurlbut| first = Cornelius S.| author2 = Klein, Cornelis| year = 1985| title = Manual of Mineralogy| edition = 20th| publisher = Wiley| isbn = 0-47180580-7| url = https://archive.org/details/manualofmineralo00klei}}</ref>

In [[mineralogy]], the crystalline forms of [[silica]] ({{chem2|SiO2}}) are usually considered to be [[Silicate mineral#Tectosilicates|tectosilicates]], and they are classified as such in the Dana system (75.1). However, the Nickel-Strunz system classifies them as [[oxide mineral]]s (4.DA). Silica is found in nature as the mineral [[quartz]] and its [[polymorphism (materials science)|polymorphs]].

On Earth, a wide variety of silicate minerals occur in an even wider range of combinations as a result of the processes that have been forming and re-working the crust for billions of years. These processes include partial [[melting]], [[crystallization]], [[fractionation]], [[metamorphism]], [[weathering]], and [[diagenesis]].

[[File:Diatomaceous Earth BrightField.jpg|thumb|right|Diatomaceous earth, a biogenic form of silica as viewed under a microscope. The imaged region measures approximately 1.13 by 0.69 mm.]]
Living organisms also contribute to this [[carbonate–silicate cycle|geologic cycle]]. For example, a type of [[plankton]] known as [[diatom]]s construct their [[exoskeleton]]s ("frustules") from silica extracted from [[seawater]]. The frustules of dead diatoms are a major constituent of [[deep ocean]] [[sediment]], and of [[diatomaceous earth]].{{Citation needed|date=April 2019}}

==General structure==
A silicate mineral is generally an [[inorganic compound]] consisting of subunits with the formula [SiO<sub>2+''n''</sub>]<sup>2''n''−</sup>.  Although depicted as such, the description of silicates as anions is a simplification.  Balancing the charges of the silicate anions are metal cations, M<sup>''x''+</sup>.  Typical cations are Mg<sup>2+</sup>, Fe<sup>2+</sup>, and Na<sup>+</sup>.  The Si-O-M linkage between the silicates and the metals are strong, polar-covalent bonds.  Silicate anions ([SiO<sub>2+''n''</sub>]<sup>2''n''−</sup>) are invariably colorless, or when crushed to a fine powder, white.  The colors of silicate minerals arise from the metal component, commonly iron.

In most silicate minerals, silicon is tetrahedral, being surrounded by four oxides.  The [[coordination number]] of the oxides is variable except when it bridges two silicon centers, in which case the oxide has a coordination number of two.

Some silicon centers may be replaced by atoms of other elements, still bound to the four corner oxygen corners. If the substituted atom is not normally tetravalent, it usually contributes extra charge to the anion, which then requires extra [[cation]]s. For example, in the mineral [[orthoclase]] {{chem|[KAlSi|3|O|8|]|''n''}}, the anion is a tridimensional network of tetrahedra in which all oxygen corners are shared. If all tetrahedra had silicon centers, the anion would be just neutral silica {{chem|[SiO|2|]|''n''}}. Replacement of one in every four silicon atoms by an [[aluminum]] atom results in the anion {{chem|[AlSi|3|O|8|−|]|''n''}}, whose charge is neutralized by the [[potassium]] cations {{chem|K|+}}.

==Main groups==
In [[mineralogy]], silicate minerals are classified into seven major groups according to the structure of their silicate anion:<ref>Deer, W.A.; Howie, R.A., & Zussman, J. (1992). ''An introduction to the rock forming minerals'' (2nd edition ed.). London: Longman {{ISBN|0-582-30094-0}}</ref><ref>Hurlbut, Cornelius S.; Klein, Cornelis ||1985). ''Manual of Mineralogy'', Wiley, (20th edition ed.). {{ISBN|0-471-80580-7}}</ref>
{| class=wikitable
! Major group !! Structure !! Chemical formula !! Example
|-
| [[Nesosilicate]]s ||isolated silicon tetrahedra || [SiO<sub>4</sub>]<sup>4−</sup> || [[olivine]], [[garnet]], [[zircon]]...
|-
| [[Sorosilicate]]s ||double tetrahedra || [Si<sub>2</sub>O<sub>7</sub>]<sup>6−</sup> || [[epidote]], [[melilite]] group
|-
| [[Cyclosilicate]]s ||rings || [Si<sub>''n''</sub>O<sub>3''n''</sub>]<sup>2''n''−</sup> || [[beryl]] group, [[tourmaline]] group
|-
| [[Inosilicate]]s ||single chain || [Si<sub>''n''</sub>O<sub>3''n''</sub>]<sup>2''n''−</sup> || [[pyroxene]] group
|-
| [[Inosilicate]]s ||double chain || [Si<sub>4''n''</sub>O<sub>11''n''</sub>]<sup>6''n''−</sup> || [[amphibole]] group
|-
| [[Silicate minerals#Phyllosilicates|Phyllosilicate]]s ||sheets || [Si<sub>2''n''</sub>O<sub>5''n''</sub>]<sup>2''n''−</sup> || [[mica]]s and [[clay]]s
|-
| [[Tectosilicate]]s ||3D framework || [Al<sub>''x''</sub>Si<sub>''y''</sub>O<sub>(2''x''+2''y'')</sub>]<sup>''x''−</sup> || [[quartz]], [[feldspar]]s, [[zeolite]]s
|}
Tectosilicates can only have additional cations if some of the silicon is replaced by an atom of lower valence such as aluminum. Al for Si substitution is common.

==Nesosilicates or orthosilicates==
[[File:Silicate-tetrahedron-3D-balls.png|thumb|Orthosilicate anion {{chem|SiO|4|4-}}. The grey ball represents the silicon atom, and the red balls are the oxygen atoms.]]
[[File:Nesosilicates exhibit, Museum of Geology, South Dakota.jpg|thumb|Nesosilicate specimens at the Museum of Geology in South Dakota]]
{{main category|Nesosilicates}}
Nesosilicates (from Greek {{wikt-lang|grc|νῆσος}} {{Transliteration|grc|nēsos}} 'island'), or orthosilicates, have the [[Orthosilicate (ion)|orthosilicate ion]], present as isolated (insular) {{chem2|[SiO4](4−)}} [[Tetrahedral molecular geometry|tetrahedra]] connected only by interstitial [[cation]]s. The [[Nickel–Strunz classification]] is 09.A –examples include:

*Phenakite group
**[[Phenakite]] – {{chem2|Be2SiO4}}
**[[Willemite]] – {{chem2|Zn2SiO4}}
*[[Olivine]] group
**[[Forsterite]] – {{chem2|Mg2SiO4}}
**[[Fayalite]] – {{chem2|Fe2SiO4}}
**[[Tephroite]] – {{chem2|Mn2SiO4}}
*[[Garnet]] group
**[[Pyrope]] – {{chem2|Mg3Al2(SiO4)3}}
**[[Almandine]] – {{chem2|Fe3Al2(SiO4)3}}
**[[Spessartine]] – {{chem2|Mn3Al2(SiO4)3}}
**[[Grossular]] – {{chem2|Ca3Al2(SiO4)3}}
**[[Andradite]] – {{chem2|Ca3Fe2(SiO4)3}}
**[[Uvarovite]] – {{chem2|Ca3Cr2(SiO4)3}}
**[[Hydrogrossular]] – {{chem|Ca|3|Al|2|Si|2|O|8|(SiO|4|)|3−''m''|(OH)|4''m''|}}
*Zircon group
**[[Zircon]] – {{chem2|ZrSiO4}}
**[[Thorite]] – {{chem2|(Th,U)SiO4}}
**[[Hafnon]] – {{chem2|(Hf,Zr)SiO4}}
[[Image:Kyanite crystals.jpg|thumb|[[Kyanite]] crystals (unknown scale)]]
*{{chem2|Al2SiO5}} group
**[[Andalusite]] – {{chem2|Al2SiO5}}
**[[Kyanite]] – {{chem2|Al2SiO5}}
**[[Sillimanite]] – {{chem2|Al2SiO5}}
**[[Dumortierite]] – {{chem|Al|6.5–7|BO|3|(SiO|4|)|3|(O,OH)|3}}
**[[Topaz]] – {{chem2|Al2SiO4(F,OH)2}}
**[[Staurolite]] – {{chem2|Fe2Al9(SiO4)4(O,OH)2}}
*[[Humite]] group – {{chem2|(Mg,Fe)7(SiO4)3(F,OH)2}}
**[[Norbergite]] – {{chem2|Mg3(SiO4)(F,OH)2}}
**[[Chondrodite]] – {{chem2|Mg5(SiO4)2(F,OH)2}}
**[[Humite]] – {{chem2|Mg7(SiO4)3(F,OH)2}}
**[[Clinohumite]] – {{chem2|Mg9(SiO4)4(F,OH)2}}
*[[Datolite]] – {{chem2|CaBSiO4(OH)}}
*[[Titanite]] – {{chem2|CaTiSiO5}}
*[[Chloritoid]] – {{chem2|(Fe,Mg,Mn)2Al4Si2O10(OH)4}}
*[[Mullite]] (aka Porcelainite) – {{chem2|Al6Si2O13}}

==Sorosilicates==
[[File:Silicate-double-tetrahedra-3D-balls.png|thumb|Pyrosilicate anion {{chem|Si|2|O|7|6-}}]]
[[File:Sorosilicates exhibit, Museum of Geology, South Dakota.jpg|thumb|Sorosilicate exhibit at Museum of Geology in South Dakota]]
{{main category|Sorosilicates}}
Sorosilicates (from Greek {{wikt-lang|grc|σωρός}} {{Transliteration|grc|sōros}} 'heap, mound') have isolated [[pyrosilicate]] anions {{chem|Si|2|O|7|6-}}, consisting of double tetrahedra with a shared oxygen vertex—a silicon:oxygen ratio of 2:7. The Nickel–Strunz classification is 09.B. Examples include:

*[[Thortveitite]] – {{chem2|(Sc,Y)2(Si2O7)}}
*[[Hemimorphite]] ([[Calamine (mineral)|calamine]]) – {{chem2|Zn4(Si2O7)(OH)2*H2O}}
*[[Lawsonite]] – {{chem2|CaAl2(Si2O7)(OH)2*H2O}}
*[[Axinite]] – {{chem2|(Ca,Fe,Mn)3Al2(BO3)(Si4O12)(OH)}}
*[[Ilvaite]] – {{chem2|CaFe^{II}2Fe^{III}O(Si2O7)(OH)}}
*Epidote group (has both {{chem2|(SiO4)(4−)}} and {{chem2|(Si2O7)(6−)}} groups}
**[[Epidote]] – {{chem2|Ca2(Al,Fe)3O(SiO4)(Si2O7)(OH)}}
**[[Zoisite]] – {{chem2|Ca2Al3O(SiO4)(Si2O7)(OH)}}
***[[Tanzanite]] – {{chem2|Ca2Al3O(SiO4)(Si2O7)(OH)}}
**[[Clinozoisite]] – {{chem2|Ca2Al3O(SiO4)(Si2O7)(OH)}}
**[[Allanite]] – {{chem2|Ca(Ce,La,Y,Ca)Al2(Fe^{II},Fe^{III})O(SiO4)(Si2O7)(OH)}}
**[[Dollaseite-(Ce)]] – {{chem2|CaCeMg2AlSi3O11F(OH)}}
*[[Vesuvianite]] ([[Vesuvianite|idocrase]]) – {{chem2|Ca10(Mg,Fe)2Al4(SiO4)5(Si2O7)2(OH)4}}

==Cyclosilicates==
<!-- This section is linked from [[Beryl]] -->
{{main category|Cyclosilicates}}
[[File:Cyclosilicate exhibit, Museum of Geology, South Dakota.jpg|thumb|Cyclosilicate specimens at the Museum of Geology, South Dakota]]
[[File:Pezzottaite-256889.jpg|thumb|[[Pezzottaite]]]]
[[File:Bazzite - Fibbia Ticino Switzerland.jpg|thumb|[[Bazzite]]]]

Cyclosilicates (from Greek {{wikt-lang|grc|κύκλος}} {{Transliteration|grc|kýklos}} 'circle'), or ring silicates, have three or more tetrahedra linked in a ring. The general formula is (Si<sub>''x''</sub>O<sub>3''x''</sub>)<sup>2''x''−</sup>, where one or more silicon atoms can be replaced by other 4-coordinated atom(s). The silicon:oxygen ratio is 1:3. Double rings have the formula (Si<sub>2''x''</sub>O<sub>5''x''</sub>)<sup>2''x''−</sup> or a 2:5 ratio. The Nickel–Strunz classification is 09.C. Possible ring sizes include:

<gallery>
File:Beryll.ring.combined.png|6 units {{chem2|[Si6O18]}}, [[beryl]] (red: Si, blue: O)
File:Benitoid.2200.png|3 units {{chem2|[Si3O9]}}, [[benitoite]]
File:Papagoite.2200.png|4 units {{chem2|[Si4O12]}}, [[papagoite]]
File:Eudialyte.2200.png|9 units {{chem2|[Si9O27]}}, [[eudialyte]]
File:Milarite.png|12 units, double ring {{chem2|[Si12O30]}}, [[milarite]]
</gallery>

Some example minerals are:
* 3-member single ring
** [[Benitoite]] – {{chem2|BaTi(Si3O9)}}
* 4-member single ring
** [[Papagoite]] – {{chem|CaCuAlSi|2|O|6|(OH)|3}}.
* 6-member single ring
**[[Beryl]] – {{chem2|Be3Al2(Si6O18)}}
**[[Bazzite]] – {{chem2|Be3Sc2(Si6O18)}}
**[[Sugilite]] – {{chem2|KNa2(Fe,Mn,Al)2Li3Si12O30}}
**[[Tourmaline]] – {{chem|(Na,Ca)(Al,Li,Mg)|3–|(Al,Fe,Mn)|6|(Si|6|O|18|)(BO|3|)|3|(OH)|4|}}
**[[Pezzottaite]] – {{chem2|Cs(Be2Li)Al2Si6O18}}
**[[Osumilite]] – {{chem2|(K,Na)(Fe,Mg)2(Al,Fe)3(Si,Al)12O30}}
**[[Cordierite]] – {{chem2|(Mg,Fe)2Al4Si5O18}}
**[[Sekaninaite]] – {{chem2|(Fe^{+2},Mg)2Al4Si5O18}}
* 9-member single ring
** [[Eudialyte]] – {{chem|Na|15|Ca|6|(Fe,Mn)|3|Zr|3|SiO|(O,OH,H|2|O)|3|(Si|3|O|9|)|2}}{{chem|(Si|9|O|27|)|2|(OH,Cl)|2}}
* 6-member double ring
**[[Milarite]] – {{chem2|K2Ca4Al2Be4(Si24O60)H2O}}

The ring in [[axinite]] contains two B and four Si tetrahedra and is highly distorted compared to the other 6-member ring cyclosilicates.

==Inosilicates==
{{main category|Inosilicates}}
Inosilicates (from Greek {{wikt-lang|grc|ἴς}} {{Transliteration|grc|is}} [genitive: {{wikt-lang|grc|ἰνός}} {{Transliteration|grc|inos}}] 'fibre'), or chain silicates, have interlocking chains of [[silicon|silicate]] [[tetrahedra]] with either {{chem2|SiO3}}, 1:3 ratio, for single chains or {{chem2|Si4O11}}, 4:11 ratio, for double chains. The Nickel–Strunz classification is 09.D – examples include:

===Single chain inosilicates===
*[[Pyroxene]] group
**Enstatite – orthoferrosilite series
***[[Enstatite]] – {{chem2|MgSiO3}}
***[[Ferrosilite]] – {{chem2|FeSiO3}}
**[[Pigeonite]] – {{chem2|Ca0.25(Mg,Fe)1.75Si2O6}}
**Diopside – hedenbergite series
***[[Diopside]] – {{chem2|CaMgSi2O6}}
***[[Hedenbergite]] – {{chem2|CaFeSi2O6}}
***[[Augite]] – {{chem2|(Ca,Na)(Mg,Fe,Al)(Si,Al)2O6}}
**Sodium pyroxene series
***[[Jadeite]] – {{chem2|NaAlSi2O6}}
***[[Aegirine]] (or acmite) – {{chem2|NaFe^{III}Si2O6}}
**[[Spodumene]] – {{chem2|LiAlSi2O6}}
**[[Pyroxferroite]] - {{chem2|(Fe,Ca)SiO3}}
*Pyroxenoid group
**[[Wollastonite]] – {{chem2|CaSiO3}}
**[[Rhodonite]] – {{chem2|MnSiO3}}
**[[Pectolite]] – {{chem2|NaCa2(Si3O8)(OH)}}

===Double chain inosilicates===
*[[Amphibole]] group
**[[Anthophyllite]] – {{chem2|(Mg,Fe)7Si8O22(OH)2}}
**Cummingtonite series
***[[Cummingtonite]] – {{chem2|Fe2Mg5Si8O22(OH)2}}
***[[Grunerite]] – {{chem2|Fe7Si8O22(OH)2}}
**Tremolite series
***[[Tremolite]] – {{chem2|Ca2Mg5Si8O22(OH)2}}
***[[Actinolite]] – {{chem2|Ca2(Mg,Fe)5Si8O22(OH)2}}
**[[Hornblende]] – {{chem|(Ca,Na)|2–3|(Mg,Fe,Al)|5|Si|6|(Al,Si)|2|O|22|(OH)|2|}}
**Sodium amphibole group
***[[Glaucophane]] – {{chem2|Na2Mg3Al2Si8O22(OH)2}}
***[[Riebeckite]] ([[asbestos]]) – {{chem2|Na2Fe^{II}3Fe^{III}2Si8O22(OH)2}}
***[[Arfvedsonite]] – {{chem2|Na3(Fe,Mg)4FeSi8O22(OH)2}}

<gallery>
File:Pyroxen-chain.png|Inosilicate, pyroxene family, with 2-periodic single chain {{chem2|(Si2O6)}}, [[diopside]]
File:Tremolite-chain.png|Inosilicate, clinoamphibole, with 2-periodic double chains {{chem2|(Si4O11)}}, [[tremolite]]
File:Wollastonite-chain.png|Inosilicate, unbranched 3-periodic single chain of [[wollastonite]]
File:Rhodonite-chain.png|Inosilicate with 5-periodic single chain, [[rhodonite]]
File:Pellyite-chain.png|Inosilicate with cyclic branched 8-periodic chain, [[pellyite]]
</gallery>

==Phyllosilicates==<!-- [[Phyllosilicate]] and [[Sheet silicate]] redirect here. -->
{{main category|Phyllosilicates}}
'''Phyllosilicates''' (from Greek {{wikt-lang|grc|φύλλον}} {{Transliteration|grc|phýllon}} 'leaf'), or sheet silicates, form parallel sheets of silicate tetrahedra with {{chem2|Si2O5}} or a 2:5 ratio. The Nickel–Strunz classification is 09.E. All phyllosilicate minerals are [[hydrate]]d, with either [[water]] or [[hydroxyl]] groups attached. Many phyllosilicates are clay-forming and may be further classified as 1:1 clay minerals (one tetrahedral sheet and one octahedral sheet) and 2:1 clay minerals (one octahedral sheet between two tetrahedral sheets). Below is a list of phyllosilicate minerals and their chemical formulas, organized by mineralogical group:
[[Image:KaolinUSGOV.jpg|thumb|Kaolinite]]
*[[Chlorite group]]<ref>{{cite web |title=Chlorite Group |url=https://www.mindat.org/min-1016.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=1 July 2025}}</ref> – {{chem2|(Al,Fe^{2+},Fe^{3+}Li,Mg,Mn,Ni)_{5-6}(Al,Fe^{3+},Si)4(O,OH)18}}{{quad}}(2:1:1 clays)
**[[Chamosite]] – {{chem2|(Fe^{2+},Mg,Al,Fe^{3+})6(Si,Al)4O10(OH,O)8}}{{quad}}(Fe endmember)
**[[Clinochlore]] – {{chem2|Mg5Al(AlSi3O10)(OH)8}}{{quad}}(Mg endmember)
**[[Cookeite]] – {{chem2|(LiAl4◻)[AlSi3O10](OH)8}}
*Kaolinite-Serpentine group<ref>{{cite web |title=Kaolinite-Serpentine Group |url=https://www.mindat.org/min-11136.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=25 June 2025}}</ref>
**Kaolinite subgroup{{quad}}(1:1 clays)
***[[Dickite]] – {{chem2|Al2(Si2O5)(OH)4}}
***[[Kaolinite]] – {{chem2|Al2Si2O5(OH)4}}
***[[Halloysite]] – {{chem2|Al2Si2O5(OH)4}}
**[[Serpentine subgroup]]
***[[Amesite]] – {{chem2|Mg2Al(AlSiO5)(OH)4}}
***[[Antigorite]] – {{chem2|Mg3Si2O5(OH)4}}
****[[Bowenite]] – {{chem2|Mg3(Si2O5)(OH)4}}{{quad}}(yellow-green variety of antigorite)<ref>{{cite web |title=Bowenite |url=https://www.mindat.org/min-744.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=25 June 2025}}</ref>
***[[Chrysotile]] – {{chem2|Mg3Si2O5(OH)4}}
***[[Cronstedtite]] – {{chem2|Fe^{2+}2Fe^{3+}((Si,Fe^{3+})2O5)(OH)4}}
***[[Lizardite]] – {{chem2|Mg3Si2O5(OH)4}}
***[[Népouite]] – {{chem2|Ni3Si2O5(OH)4}}
***[[Pecoraite]] – {{chem2|Ni3(Si2O5)(OH)4}}
*[[Mica]] group<ref>{{cite web |title=Mica Group |url=https://www.mindat.org/min-6728.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=24 February 2025}}</ref>
**Brittle mica group<ref>{{cite web |title=Brittle Mica |url=https://www.mindat.org/min-43757.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=24 February 2025}}</ref>
***[[Anandite]] – {{chem2|(Ba,K)(Fe^{2+},Mg)3((Si,Al,Fe)4O10)(S,OH)2}}
***[[Bityite]] – {{chem2|CaLiAl2(AlBeSi2O10)(OH)2}}
***[[Clintonite]] – {{chem2|CaAlMg2(SiAl3O10)(OH)2}}
***[[Margarite]] – {{chem2|CaAl2(Al2Si2)O10(OH)2}}
**Dioctahedral mica group
***Celadonite subgroup
****[[Aluminoceladonite]] – {{chem2|K(MgAl◻)(Si4O10)(OH)2}}
****[[Celadonite]] – {{chem2|K(MgFe^{3+}◻)(Si4O10)(OH)2}}
***[[Glauconite]] – {{chem2|K_{0.60-0.85}(Fe^{3+},Mg,Al)2(Si,Al)4O10](OH)2}}
***[[Muscovite]] – {{chem2|KAl2(AlSi3)O10(OH)2}}<ref>{{cite web |title=Muscovite |url=https://www.mindat.org/min-2815.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=24 February 2025}}</ref>
****[[Fuchsite]] – {{chem2|K(Al,Cr)3Si3O10(OH)2}}{{quad}}(Cr replaces Al in muscovite)<ref>{{cite web |title=Fuchsite |url=https://www.mindat.org/min-1617.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=24 February 2025}}</ref>
****[[Illite]] – {{chem2|K_{0.6-0.85}(Al,Mg)2(Si,Al)4O10(OH)2}}{{quad}}(K-deficient muscovite)<ref>{{cite web |title=Illite |url=https://www.mindat.org/min-2011.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=24 February 2025}}</ref>{{quad}}(2:1 clay)
****[[Mariposite]] – {{chem2|K(Al,Cr)2(Al,Si)4O10(OH)2}}{{quad}}(Cr-bearing muscovite)<ref>{{cite web |title=Mariposite |url=https://www.mindat.org/min-10003.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=24 February 2025}}</ref>
****[[Phengite]] – {{chem2|KAl1.5(Mg,Fe)0.5(Al0.5Si3.5O10)(OH)2}}{{quad}}(Fe/Mg-bearing muscovite)<ref>{{cite web |title=Phengite |url=https://www.mindat.org/min-3189.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=16 March 2025}}</ref>
***[[Paragonite]] – {{chem2|NaAl2(AlSi3O10)(OH)2}}
***[[Roscoelite]] – {{chem2|K(V^{3+},Al)2(AlSi3O10)(OH)2}}
**Trioctahedral mica group
***[[Aspidolite]] – {{chem2|NaMg3(AlSi3O10)(OH)2}}
***[[Biotite]] subgroup – {{chem2|K(Fe^{2+},Mg)2(Al,Fe^{3+},Mg,Ti)([Si,Al,Fe]2Si2O10)(OH,F)2}}
****[[Annite]] – {{chem2|KFe^{2+}3(AlSi3O10)(OH)2}}{{quad}}(Fe endmember)
****[[Phlogopite]] – {{chem2|KMg3(AlSi3)O10(OH)2}}{{quad}}(Mg endmember)
***[[Hendricksite]] – {{chem2|KZn3(Si3Al)O10(OH)2}}
***[[Lepidolite]] (polylithionite-trilithionite series) – {{chem2|K(Li2,Li1.5Al1.5)AlSi_{3-4}O10(F,OH)2}}
***[[Zinnwaldite]] series – {{chem2|KFe^{2+}2Al(Al2Si2O10)(OH)2}}
*[[Sepiolite]] – {{chem2|Mg4(Si6O15)(OH)2 · 6H2O}}<ref>{{cite web |title=Sepiolite |url=https://www.mindat.org/min-3621.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=1 July 2025}}</ref>{{quad}}(2:1 clay)
*Smectite group<ref>{{cite web |title=Smectite Group |url=https://www.mindat.org/min-11119.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=25 June 2025}}</ref>{{quad}}(2:1 clays)
**[[Aliettite]] – {{chem2|Ca0.2Mg6((Si,Al)8O20)(OH)4 · 4H2O}}<ref>{{cite web |title=Aliettite |url=https://www.mindat.org/min-115.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=25 June 2025}}</ref>
**[[Hectorite]] – {{chem2|Na0.3(Mg,Li)3(Si4O10)(F,OH)2}}
**[[Montmorillonite]] – {{chem2|(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O}}
**[[Nontronite]] – {{chem2|Na0.3Fe2((Si,Al)4O10)(OH)2 · nH2O}}
**[[Saliotite]] – {{chem2|(Li,Na)Al3(AlSi3O10)(OH)5}}
**[[Saponite]] – {{chem2|Ca0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O}}
**[[Sauconite]] – {{chem2|Na0.3Zn3((Si,Al)4O10)(OH)2 · 4H2O}}
**[[Stevensite]] – {{chem2|(Ca,Na)_{x}Mg_{3-x}(Si4O10)(OH)2}}
*[[Palygorskite]] (or attapulgite) – {{chem2|◻Al2Mg2◻2Si8O20(OH)2(H2O)4 · 4H2O}}<ref>{{cite web |title=Palygorskite |url=https://www.mindat.org/min-3072.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=1 July 2025}}</ref>{{quad}}(2:1 clay)
*Pyrophyllite-Talc group<ref>{{cite web |title=Pyrophyllite-Talc Group |url=https://www.mindat.org/min-39702.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=26 June 2025}}</ref>
**[[Minnesotaite]] – {{chem2|Fe^{2+}3Si4O10(OH)2}}
**[[Pyrophyllite]] – {{chem2|Al2Si4O10(OH)2}}
**[[Talc]] – {{chem2|Mg3Si4O10(OH)2}}{{quad}}(2:1 clay)
*[[Vermiculite]] – {{chem2|Mg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O}}<ref>{{cite web |title=Vermiculite |url=https://www.mindat.org/min-4170.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=1 July 2025}}</ref>{{quad}}(2:1 clay)

<gallery>
File:Muskovite.sheet.png|Phyllosilicate, mica group, [[muscovite]] (red: Si, blue: O)
File:Apophyllite.sheet.png|Phyllosilicate, single net of tetrahedra with 4-membered rings, [[apophyllite]]-(KF)-apophyllite-(KOH) series
File:Pyrosmalite.sheet.png|Phyllosilicate, single tetrahedral nets of 6-membered rings, [[pyrosmalite]]-(Fe)-pyrosmalite-(Mn) series
File:Zeophyllite.sheet.png|Phyllosilicate, single tetrahedral nets of 6-membered rings, [[zeophyllite]]
File:Carletonite.sheet.png|Phyllosilicate, double nets with 4- and 6-membered rings, [[carletonite]]
</gallery>

== Tectosilicates ==
{{main category|Tectosilicates}}
[[File:Beta-quartz-CM-2D-balls.png|thumb|Silica family {{chem2|(SiO2}} 3D network), β-[[quartz]]]]
[[File:Zeolite-ZSM-5-vdW.png|thumb|Aluminosilicate family, the 3D model of synthetic [[zeolite]] ZSM-5]]
[[Image:Quartz oisan.jpg|thumb|[[Quartz]]]]
[[Image:Lunar Ferroan Anorthosite (60025).jpg|thumb|[[Moon|Lunar]] ferroan [[anorthosite]] ([[plagioclase]] feldspar) collected by [[Apollo 16]] astronauts from the [[Geology of the Moon#Highlands|Lunar Highlands]] near [[Descartes (crater)|Descartes Crater]]]]
Tectosilicates, or "framework silicates," have a three-dimensional framework of silicate [[tetrahedra]] with {{chem2|SiO2}} in a 1:2 ratio. This group comprises nearly 75% of the [[crust (geology)|crust]] of the [[Earth]].<ref name=deer4B>{{Cite book| last = Deer| first = W.A. |author2=Howie, R.A. |author3=Wise, W.S. |author4=Zussman, J.| year = 2004| title = Rock-forming minerals. Volume 4B. Framework silicates: silica minerals. Feldspathoids and the zeolites| edition = 2nd| publisher = Geological Society of London| location = London| page = 982 pp}}</ref> Tectosilicates, with the exception of the quartz group, are [[aluminosilicate]]s. The Nickel–Strunz classifications are 9.F (tectosilicates without zeolitic {{chem2|H2O}}), 9.G (tectosilicates with zeolitic {{chem2|H2O}}), and 4.DA (quartz/silica group). Below is a list of tectosilicate minerals and their chemical formulas, organized by mineralogical group:
*Quartz group ([[Silicon dioxide|silica]]) – {{chem2|SiO2}}
**[[Quartz|α-quartz]] – [[trigonal]], quartz under {{convert|573|C|K F}}
**[[Quartz|β-quartz]] – [[Hexagonal crystal family|hexagonal]], high-temperature quartz
**[[Coesite]] – [[Monoclinic crystal system|monoclinic]] [[Crystal polymorphism|polymorph]]
**[[Cristobalite]] – [[Tetragonal crystal system|tetragonal]] polymorph
**[[Moganite]] – monoclinic polymorph
**[[Stishovite]] – hard and dense tetragonal polymorph
**[[Tridymite]] – [[Orthorhombic crystal system|orthorhombic]] polymorph
*[[Feldspar]] group<ref>{{cite web |title=Feldspar Group |url=https://www.mindat.org/min-1624.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=23 February 2025}}</ref>
**Alkali feldspar series (potassium feldspars or K-spar)
***[[Microcline]] – {{chem2|KAlSi3O8}}
***[[Orthoclase]] – {{chem2|KAlSi3O8}}
***[[Anorthoclase]] – {{chem2|(Na,K)AlSi3O8}}
***[[Sanidine]] – {{chem2|KAlSi3O8}}
**[[Plagioclase]] feldspar series
***[[Albite]] – {{chem2|NaAlSi3O8}}{{quad}}(Na endmember)
***[[Oligoclase]] – {{chem2|(Na,Ca)Al(Si,Al)Si2O8}}{{quad}}(Na:Ca 90:10 to 70:30)<ref>{{cite web |title=Oligoclase |url=https://www.mindat.org/min-2976.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=23 February 2025}}</ref>
***[[Andesine]] – {{chem2|(Na,Ca)Al(Si,Al)Si2O8}}{{quad}}(Na:Ca 50:50 to 70:30)<ref>{{cite web |title=Andesine |url=https://www.mindat.org/min-220.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=23 February 2025}}</ref>
***[[Labradorite]] – {{chem2|(Ca,Na)Al(Al,Si)Si2O8}}{{quad}}(Na:Ca 30:70 to 50:50)<ref>{{cite web |title=Labradorite |url=https://www.mindat.org/min-2308.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=23 February 2025}}</ref>
***[[Bytownite]] – {{chem2|(Ca,Na)Al(Al,Si)Si2O8}}{{quad}}(Na:Ca 10:90 to 30:70)<ref>{{cite web |title=Bytownite |url=https://www.mindat.org/min-815.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=23 February 2025}}</ref>
***[[Anorthite]] – {{chem2|CaAl2Si2O8}}{{quad}}(Ca endmember)
**Other feldspars
***[[Buddingtonite]] — {{chem2|NH4AlSi3O8}}
***[[Celsian]] – {{chem2|BaAl2Si2O8}}
***[[Hyalophane]] – {{chem2|(K,Ba)[Al(Si,Al)Si2O8]}}<ref>{{cite web |title=Hyalophane |url=https://www.mindat.org/min-1960.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=23 February 2025}}</ref>
***[[Rubicline]] – {{chem2|(RbAlSi3O8}}<ref>{{cite web |title=Rubicline |url=https://www.mindat.org/min-7276.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=23 February 2025}}</ref>
*[[Feldspathoid]] group<ref>{{cite web |title=Feldspathoid |url=https://www.mindat.org/min-47865.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=23 February 2025}}</ref>
**Cancrinite subgroup
***[[Afghanite]] – {{chem2|(Na,K)22Ca10[Si24Al24O96](SO4)6Cl6}}
***[[Alloriite]] – {{chem2|(Na,Ca,K)26Ca4(Al6Si6O24)4(SO4)6Cl6}}
***[[Bystrite]] – {{chem2|(Na,K)7Ca(Al6Si6O24)(S5)Cl}}
***[[Cancrinite]] – {{chem2|(Na,Ca,◻)8(Al6Si6O24)(CO3,SO4)2*2H2O}}
***[[Farneseite]] – {{chem2|(Na,Ca,K)56(Al6Si6O24)7(SO4)12*6H2O}}
***[[Sacrofanite]] – {{chem2|(Na61K19Ca32)(Si84Al84O336)(SO4)26Cl2F6*2H2O}}
***[[Vishnevite]] – {{chem2|(Na,K)8(Al6Si6O24)(SO4,CO3)*2H2O}}
**[[Danalite]] – {{chem2|Be3Fe²⁺4(SiO4)3S}}<ref>{{cite web |title=Danalite |url=https://www.mindat.org/min-1341.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=23 February 2025}}</ref>
**[[Kalsilite]] – {{chem2|KAlSiO4}}
**[[Leucite]] – {{chem2|K(AlSi2O6)}}
**Nepheline subgroup
***[[Davidsmithite]] – {{chem2|(Ca,◻)2Na6Al8Si8O32}}
***[[Nepheline]] – {{chem2|Na3K(Al4Si4O16)}}
**Sodalite subgroup
***[[Hauyne]] – {{chem2|Na3Ca(Si3Al3)O12(SO4)}}
***[[Lazurite]] – {{chem2|Na7Ca(Al6Si6O24)(SO4)(S3)*H2O}}
***[[Nosean]] – {{chem2|Na8(Al6Si6O24)(SO4)*H2O}}
***[[Sodalite]] – {{chem2|Na4(Si3Al3)O12Cl}}
***[[Tugtupite]] – {{chem2|Na4(BeAlSi4O12)Cl}}<ref>{{cite web |title=Tugtupite |url=https://www.mindat.org/min-4044.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=23 February 2025}}</ref>
*[[Scapolite]] group<ref>{{cite web |title=Scapolite |url=https://www.mindat.org/min-8778.html |website=mindat.org |publisher=Hudson Institute of Mineralogy |access-date=23 February 2025}}</ref>
**[[Marialite]] – {{chem2|Na4Al3Si9O24Cl}}
**[[Meionite]] – {{chem2|Ca4Al6Si6O24CO3}}
*[[Zeolite]] group<ref>{{Cite web |title=Zeolite Group |url=https://www.mindat.org/min-4395.html |access-date=2025-02-22 |website=www.mindat.org}}</ref>
**[[Amicite]] – {{chem2| K2Na2Al4Si4O16*5H2O}}
**[[Analcime]] – {{chem2|Na(AlSi2O6)*H2O}}
**[[Brewsterite]] subgroup – {{chem2| (Ba,Sr,Ca)Al2Si6O16*5H2O}}
**Chabazite-Lévyne subgroup
***[[Chabazite]] – {{chem2|''M''[Al2Si4O12]*6H2O}}
***[[Lévyne]] – {{chem2|(Ca_{1-2},Na_{1-2},K2)Al2Si4O12*6H2O}}
**[[Clinoptilolite]] subgroup – {{chem2|(Na,Ca,K)_{3-6}(Al_{6-7}Si_{29-30}O72)*20H2O}}
**[[Cowlesite]] – {{chem2|CaAl2Si3O10*6H2O}}
**[[Dachiardite-K]] – {{chem2| K4(Si20Al4O48)*13H2O}}
**[[Edingtonite]] – {{chem2| BaAl2Si3O10*4H2O}}
**[[Erionite]] subgroup – {{chem2|(Na_{1-2},K_{1-2},Ca_{1-2})2Al4Si14O36*15H2O}}
**[[Faujasite]] subgroup – {{chem2| (Na_{1-2},Ca_{1-2},Mg_{1-2})3.5[Al7Si17O48]*32H2O}}
**[[Ferrierite]] subgroup – {{chem2|[Mg2(K,Na)2Ca0.5](Si29Al7)O72*18H2O}}{{quad}}(Ferrierite-Mg)
**[[Garronite-Ca]] – {{chem2|Na2Ca5Al12Si20O64*27H2O}}
**[[Gismondine]] – {{chem2|CaAl2Si2O8*4H2O}}{{quad}}(Gismondine-Ca)
**[[Gmelinite]] subgroup – {{chem2|Na4(Si8Al4)O24*11H2O}}{{quad}}(Gmelinite-Na)
**[[Heulandite]] subgroup – {{chem2|(Na,Ca,K)_{5-6}[Al_{8-9}Si_{27-28}O72]*nH2O}}
**[[Hsianghualite]] – {{chem2|Ca3Li2(Be3Si3O12)F2}}
**[[Laumontite]] – {{chem2|CaAl2Si4O12*4H2O}}
**[[Mordenite]] – {{chem2|(Na2,Ca,K2)4(Al8Si40)O96*28H2O}}
**[[Nabesite]] – {{chem2|Na2BeSi4O10*4H2O}}
**Natrolite subgroup
***[[Gonnardite]] – {{chem2|(Na,Ca)2(Si,Al)5O10*3H2O}}
***[[Mesolite]] – {{chem2|Na2Ca2Si9Al6O30*8H2O}}
***[[Natrolite]] – {{chem2|Na2Al2Si3O10*2H2O}}
***[[Scolecite]] – {{chem2|CaAl2Si3O10*3H2O}}
**[[Paulingite]] subgroup – {{chem2|(K2,Ca,Na2,Ba)5[Al10Si35O90]*45H2O}}{{quad}}(Paulingite-K)
**Phillipsite subgroup
***[[Harmotome]] – {{chem2|(Ba2(Si12Al4)O32*12H2O}}
***[[Phillipsite]] – {{chem2|(Ca3(Si10Al6)O32*12H2O}}{{quad}}(Phillipsite-Ca)
**[[Pollucite]] – {{chem2|(Cs,Na)2(Al2Si4O12)*2H2O}}
**Stilbite subgroup
***[[Barrerite]] – {{chem2| Na2(Si7Al2)O18*6H2O}}
***[[Stellerite]] – {{chem2|Ca4(Si28Al8)O72*28H2O}}
***[[Stilbite]] – {{chem2|(NaCa4,Na9)(Si27Al9)O72*28H2O}}
**[[Thomsonite]] subgroup – {{chem2|NaCa2Al5Si5O20*6H2O}}{{quad}}(Thomsonite-Ca) 
**[[Wairakite]] – {{chem2|Ca(Al2Si4O12)*2H2O}}
**[[Yugawaralite]] – {{chem2|CaAl2Si6O16*4H2O}}

==See also==
{{Portal|Earth sciences}}
* {{annotated link|Classification of non-silicate minerals}}
* {{annotated link|Classification of silicate minerals}}
* {{annotated link|Silicate mineral paint}}

==References==
{{reflist}}

==External links==
{{Wikibooks|Historical Geology|Silicate minerals}}
{{Commons category|Silicate minerals}}
* [http://www.mindat.org/dana.php Mindat.org, Dana classification]
* [http://webmineral.com/dana/8_Silicates.shtml Webmineral : Dana's New Silicate Classification]

{{Strunz}}
{{Authority control}}

[[Category:Silicate minerals| ]]

[[pl:Krzemiany]]