rocks and minerals quiz 1

Nesosilicate (formula)

SiO4

Nesosilicate (examples)

Forsterite: Mg2SiO4

Fayalite: Fe2SiO4

Zircon: ZrSiO4

Garnets:

• pyrope

• Almandine

• Spessartine

• grossular

• Andradite

• Uvarovite

Sorosilicate (formula)

Si2O7

Sorosilicate (examples)

Epidote: Ca2(Al,Fe)Al2O(SiO4)(Si2O7)OH

Cyclosilicate (formula)

Si6O18

Cyclosilicate (examples)

Beryl: Be3Al2Si6O18

Tourmaline: Na(Mg,Fe)3Al6(BO3)(Si6O18)(OH)4

Inosilicate (single & double formula)

Single: Si2O6 and SiO3

Double: Si8O22

Inosilicate (examples)

Single:

• Enstatite- MgSiO3

• Ferroslite- FeSiO3

• Orthopyroxene- (Mg,Fe)2Si2O6

• Augite- Ca(Mg,Fe,Al)(Al,Si)2O6

• Diopside- CaMgSi2O6

• Jadeite- NaAlSi2O6

• Spodamene- LiAlSi2O6

• Wollastonite- CaSiO3

Double:

• Hornblende: (Na,Ca)2-3(Mg,Fe,Al)5(Al,Si)8O22(OH2)

• Tremolite/Actindite: Ca2(Mg,Fe)5Si8O22(OH2)

• Glaucophane: Na2Mg3Al2Si8O22(OH)2

Phyllosilicate (formula)

Si2O5 and Si4O10

Tectosilicate (formula)

SiO2

Cube

A=B=C

Alpha=beta=gama=90°

Tetragonal

A=B≠C

Alpha=beta=gama=90°

Orthorhombic

A≠B≠C

Alpha=beta=gama=90°

Hexagonal

A=B≠C

Alpha=beta=90°, gama=120°

Monoclinic

A≠B≠C

Alpha=gama=90°≠beta

Triclinic

A≠B≠C

Alpha≠Beta≠Gama≠90°