Silicates

54 minerals in this group.

Quartz

SiO2

H: 7SG: 2.65Trigonal

Feldspar

KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8

H: 6SG: 2.56Triclinic/Monoclinic

Mica

KAl2(AlSi3O10)(OH)2

H: 2.5SG: 2.8Monoclinic

Topaz

Al2SiO4(F,OH)2

H: 8SG: 3.53Orthorhombic

Tourmaline

Na(Li,Al)3Al6(BO3)3Si6O18(OH)4

H: 7.5SG: 3.06Trigonal

Garnet

Fe3Al2(SiO4)3 (varies)

H: 7SG: 4.32Cubic

Olivine

(Mg,Fe)2SiO4

H: 6.5SG: 3.32Orthorhombic

Augite

(Ca,Na)(Mg,Fe,Al)(Si,Al)2O6

H: 6SG: 3.26Monoclinic

Hornblende

Ca2(Mg,Fe,Al)5(Al,Si)8O22(OH)2

H: 5.5SG: 3.15Monoclinic

Muscovite

KAl2(AlSi3O10)(OH)2

H: 2.5SG: 2.82Monoclinic

Biotite

K(Fe,Mg)3AlSi3O10(OH)2

H: 2.5SG: 3.1Monoclinic

Talc

Mg3Si4O10(OH)2

H: 1SG: 2.75Monoclinic

Kaolinite

Al2Si2O5(OH)4

H: 2.5SG: 2.63Triclinic

Sphene

CaTiSiO5

H: 5.5SG: 3.53Monoclinic

Zircon

ZrSiO4

H: 7.5SG: 4.68Tetragonal

Epidote

Ca2(Al,Fe)3(SiO4)3(OH)

H: 6SG: 3.45Monoclinic

Jadeite

NaAlSi2O6

H: 7SG: 3.34Monoclinic

Nephrite

Ca2(Mg,Fe)5Si8O22(OH)2

H: 6SG: 3Monoclinic

Serpentine

Mg3Si2O5(OH)4

H: 3.5SG: 2.6Monoclinic

Tremolite

Ca2Mg5Si8O22(OH)2

H: 5.5SG: 3Monoclinic

Actinolite

Ca2(Mg,Fe)5Si8O22(OH)2

H: 5.5SG: 3.2Monoclinic

Andalusite

Al2SiO5

H: 7.5SG: 3.17Orthorhombic

Sillimanite

Al2SiO5

H: 7.5SG: 3.24Orthorhombic

Kyanite

Al2SiO5

H: 7 (varies)SG: 3.68Triclinic

Staurolite

Fe2Al9Si4O22(OH)2

H: 7SG: 3.75Monoclinic

Chlorite

(Mg,Fe)3(Si,Al)4O10(OH)2·(Mg,Fe)3(OH)6

H: 2.5SG: 2.9Monoclinic

Sodalite

Na8Al6Si6O24Cl2

H: 5.5SG: 2.3Cubic

Lapis Lazuli

(Na,Ca)8(AlSiO4)6(SO4,S,Cl)2

H: 5.5SG: 2.4Cubic

Leucite

KAlSi2O6

H: 6SG: 2.48Tetragonal

Nepheline

(Na,K)AlSiO4

H: 6SG: 2.6Hexagonal

Wollastonite

CaSiO3

H: 5SG: 2.9Triclinic

Diopside

CaMgSi2O6

H: 6SG: 3.28Monoclinic

Enstatite

MgSiO3

H: 5.5SG: 3.2Orthorhombic

Hypersthene

(Mg,Fe)SiO3

H: 5.5SG: 3.45Orthorhombic

Beryl

Be3Al2Si6O18

H: 7.5SG: 2.76Hexagonal

Emerald

Be3Al2Si6O18 (Cr/V bearing)

H: 7.5SG: 2.72Hexagonal

Aquamarine

Be3Al2Si6O18 (Fe bearing)

H: 7.5SG: 2.7Hexagonal

Amethyst

SiO2 (Fe bearing)

H: 7SG: 2.65Trigonal

Citrine

SiO2 (Fe bearing)

H: 7SG: 2.65Trigonal

Rose Quartz

SiO2 (Ti/Mn bearing)

H: 7SG: 2.65Trigonal

Smoky Quartz

SiO2 (Al bearing, irradiated)

H: 7SG: 2.65Trigonal

Agate

SiO2

H: 7SG: 2.6Trigonal

Onyx

SiO2

H: 7SG: 2.6Trigonal

Jasper

SiO2

H: 7SG: 2.65Trigonal

Chalcedony

SiO2

H: 7SG: 2.6Trigonal

Carnelian

SiO2

H: 7SG: 2.6Trigonal

Moonstone

KAlSi3O8

H: 6SG: 2.56Monoclinic

Labradorite

(Na,Ca)(Al,Si)4O8

H: 6.5SG: 2.7Triclinic

Amazonite

KAlSi3O8

H: 6SG: 2.56Triclinic

Sillimanite

Al2SiO5

H: 7SG: 3.68Triclinic

Zircon

ZrSiO4

H: 7.5SG: 4.68Tetragonal

Peridot

(Mg,Fe)2SiO4

H: 6.5SG: 3.34Orthorhombic

Tanzanite

Ca2Al3(SiO4)3(OH)

H: 6.5SG: 3.35Orthorhombic

Asbestos

Various (chrysotile, amphiboles)

H: 2.5-6SG: 2.6-3.2Various