Common rock-forming minerals

Question 1

Olivine (Mg,Fe)2SiO4
Cleavage/Fracture:
Silicate structure:
Color/Luster:

Answer 1

Cleavage/Fracture: None, conchoidal fracture
Silicate structure: single tetrahedra
Color/Luster: black to olive green, glassy

Question 2

Pyroxene group: (Mg,Fe,Ca,Na)AlSiO3
Cleavage/Fracture:
Silicate structure:
Color/Luster:

Answer 2

Cleavage/Fracture: Two planes at 90
Silicate structure: single chain
Color/Luster: black, opaque

Question 3

Amphibole group Ca2 (Fe,Mg)5Si8O22(OH)2
(Hornblende)
Cleavage/Fracture:
Silicate structure:
Color/Luster:

Answer 3

Cleavage/Fracture: Two planes at 60, 90
Silicate structure: double chain
Color/Luster: dark green to black

Question 4

Biotite K(Mg,Fe)3AlSi3O10(OH)2
Cleavage/Fracture:
Silicate structure:
Color/Luster:

Answer 4

Cleavage/Fracture: one plane
Silicate structure: sheets
Color/Luster: Dark color

Question 5

Muscovite KAl2(AlSi3O10)(OH)2
Cleavage/Fracture:
Silicate structure:
Color/Luster:

Answer 5

Cleavage/Fracture:one plane
Silicate structure: sheets
Color/Luster: pearly luster

Question 6

Potassium feldspar KAlSi3O8
(Orthoclase)
Cleavage/Fracture:
Silicate structure:
Color/Luster:

Answer 6

Cleavage/Fracture: two planes at 90
Silicate structure: three-dimensional framework
Color/Luster: pink, no striations

Question 7

Plagioclase (Ca,Na)AlSi3O8
Cleavage/Fracture:
Silicate structure:
Color/Luster:

Answer 7

Cleavage/Fracture: two planes at 90
Silicate structure: three-dimensional framework
Color/Luster: white to medium gray, with striations

Question 8

Quartz SiO2
Cleavage/Fracture:
Silicate structure:
Color/Luster:

Answer 8

Cleavage/Fracture: none, conchoidal fracture
Silicate structure: three-dimensional framework
Color/Luster: milky (white)

Question 9

Cleavage/Fracture: None, conchoidal fracture
Silicate structure: single tetrahedra
Color/Luster: black to olive green, glassy

Answer 9

Olivine (Mg,Fe)2SiO4

Question 10

Cleavage/Fracture: Two planes at 90
Silicate structure: single chain
Color/Luster: black, opaque

Answer 10

Pyroxene group: (Mg,Fe,Ca,Na)AlSiO3

Question 11

Cleavage/Fracture: Two planes at 60, 90
Silicate structure: double chain
Color/Luster: dark green to black

Answer 11

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

Question 12

Cleavage/Fracture: one plane
Silicate structure: sheets
Color/Luster: Dark color

Answer 12

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

Question 13

Cleavage/Fracture:one plane
Silicate structure: sheets
Color/Luster: pearly luster

Answer 13

Muscovite KAl2(AlSi3O10)(OH)2 (mica)

Question 14

Cleavage/Fracture: two planes at 90
Silicate structure: three-dimensional framework
Color/Luster: pink, no striations

Answer 14

Potassium feldspar KAlSi3O8 (orthoclase)

Question 15

Cleavage/Fracture: two planes at 90
Silicate structure: three-dimensional framework
Color/Luster: white to medium gray, with striations

Answer 15

Plagioclase (Ca,Na)AlSi3O8

Question 16

Cleavage/Fracture: none, conchoidal fracture
Silicate structure: three-dimensional framework
Color/Luster: milky (white)

Answer 16

Quartz SiO2

Question 17

Mt. Mayon type of volcano

Answer 17

stratovolcano

Question 18

Mt. Pinatubo type of volcano

Answer 18

caldera

Question 19

Taal volcano type of volcano

Answer 19

caldera

Question 20

how many active volcanoes?

Answer 20

24

Question 21

rate of seafloor spreading

Answer 21

5 cm/ year

Question 22

(1984 Mt. Mayon) Eruption

Answer 22

Palean type

Question 23

(1991 Mt. Pinatubo) Eruption

Answer 23

Plinian type

Question 24

mount kanlaon, mt bulusan

Answer 24

phreatic

Question 25

volcanic ash

Answer 25

less than 2 mm (0.05 in)

Question 26

lapilli (cinders)

Answer 26

2-64 mm

Question 27

volcanic bombs and volcanic block

Answer 27

more than 64 mm (2.5 in)

round, sharp