Lab 1: Silicate Group

Question 1

Quartz

Answer 1

Luster: Vitreous
Hardness: 7
Cleavage: Fracture
Formula: SiO2

Question 2

Orthoclase

Answer 2

Luster: Vitreous
Hardness: 6
Cleavage: 2 at 90 degrees
Formula: KAlSi3O8

Question 3

Plagioclase

Answer 3

Luster: Vitreous
Hardness: 6
Cleavage: 2 at 90 degrees
Formula: Ab100An0 - Ab0An100

Question 4

Muscovite

Answer 4

Luster: Vitreous
Hardness: 2 - 2.5
Cleavage: 1 Planar
Formula: KAl3Si3O10(OH)2

Question 5

Biotite

Answer 5

Luster: Vitreous
Hardness: 2.5 - 3
Cleavage: 1 Planar
Formula: K(Mg,Fe)3AlSi3O10(OH)

Question 6

Olivine

Answer 6

Luster: Vitreous
Hardness: 6.5 - 7
Cleavage: Fracture
Formula: (Mg, Fe)2SiO4

Question 7

Hornblende

Answer 7

Luster: Vitreous
Hardness: 5-6
Cleavage: 2 not at 90 degrees
Formula: (Na, K)0-1Ca2(Mg, Fe, Al)5Si6-7Al2-1O22( OH,F)2

Question 8

Actinolite

Answer 8

Luster: Vitreous
Hardness: 5-6
Cleavage: 2 at 60 degrees
Formula: Ca2Fe5Si8O22(OH)2

Question 9

Augite

Answer 9

Luster: Vitreous
Hardness: 5-6
Cleavage: 2 at 90 degrees
Formula: (Ca, Na)(Mg, Fe, Al)(Si, Al)2O6

Question 10

Diopside

Answer 10

Luster: Vitreous
Hardness: 5-6
Cleavage: 2 at 90 degrees
Formula: CaMgSi2O6

Question 11

Garnet

Answer 11

Luster: Vitreous
Hardness: 6.5 - 7
Cleavage: Fracture
Formula: A3B2(SiO4)3

Question 12

Kaolinite

Answer 12

Luster: Earthy
Hardness: 2-2.5
Cleavage: Fracture
Formula: Al2Si2O5(OH)4 (Talc Powder in Diapers)

Question 13

Serpentine

Answer 13

Luster: Waxy
Hardness: 4-5
Cleavage: Fracture
Formula: Mg3Si2O5(OH)4

Question 14

Talc

Answer 14

Luster: Pearly
Hardness: 1
Cleavage: Fracture
Formula: Mg3Si4O10(OH)2

Question 15

Chalcedony

Answer 15

Luster: Vitreous
Hardness: 6.5-7
Cleavage: Fracture
Formula: Si02 (Very fine intergrowths of Quartz + Maganite