Silicate Minerals |
1. Nesosilicates: independent tetrahedra (SiO4) |
Olivine (Forsterite-Fayalite) |
(Mg,Fe)2SiO4 |
Garnet - Almandine |
Fe3Al2Si3O12 |
Garnet - Grossularite |
Ca3Al2Si3O12 |
Kyanite, Andalusite, Sillimanite |
Al2SiO5 |
Titanite (Sphene) |
CaTiSiO5 |
Zircon |
ZrSiO4 |
2. Sorosilicate: double-tetrahedral groups (Si2O7) |
Epidote |
Ca,Fe+3, Al silicate with (OH) |
3.Cyclosilicates: rings of linked tetrahedra (Si6O18) |
Beryl |
Be3Al2Si6O18 |
Tourmaline |
Na,Mg,Fe,Al etc borosilicate with (BO3), (OH) |
Cordierite |
(Fe,Mg)2Al4Si5O18.nH2O |
4. Inosilicates: chains of linked tetrahedra |
(a) Pyroxenes - single chains (SiO3) |
Diopside |
CaMgSi2O6 |
Augite |
(Ca,Mg,Fe)2Si2O6 |
Orthopyroxene (enstatite, hypersthene) |
(Mg,Fe) SiO3 |
(b) Amphiboles - double chains (Si4O11) with (OH) |
Tremolite, Actinolite |
Ca2(Mg,Fe)5(Si8O22) (OH)2 |
Hornblende |
NaCa2(Mg,Fe)5(AlSi7O22) (OH)2 |
5. Phyllosilicates: sheets of linked tetrahedra (Si2O5) with (OH) |
Kaolinite |
Al4(Si4O10) (OH)8 |
Serpentine |
Mg6(Si4O10) (OH)8 |
Talc |
Mg3(Si4O10) (OH)2 |
Chlorite |
Mg5Al(AlSi3O10) (OH)8 |
Biotite |
K(Fe,Mg)3(AlSi3O10) (OH)2 |
Muscovite |
KAl2(AlSi3O10) (OH)2 |
6. Tectosilicates: 3-D frameworks of linked tetrahedra (SiO2 etc.) |
Quartz |
SiO2 |
Orthoclase |
KAlSi3O8 - (K, Na) AlSi3O8 |
Plagioclase (albite-anorthite) |
Anorthite |
CaAl2Si2O8 |
Albite |
NaAlSi3O8 |
