Exam 1

Question 1

hematite

Answer 1

gray metallic or red and earthy, red streak

Question 2

graphite

Answer 2

metallic, wide/rich streak, feels soft and greasy, scratch-able with fingernail

Question 3

pyrite

Answer 3

metallic, gold cubic structure, gray streak, no cleavage (fool’s gold)

Question 4

galena

Answer 4

metallic, silver cubic structure, 3 planes of cleavage 90º, very dense

Question 5

magnetite

Answer 5

metallic, magnetic, small grains

Question 6

talc

Answer 6

light color, scratch-able with fingernail, usually transparent/translucent

Question 7

gypsum

Answer 7

light color, scratch-able with fingernail, opaque

Question 8

⭐️muscovite

Answer 8

iron nail, silver, single cleavage plane, white streak (mica fam)

Question 9

⭐️biotite

Answer 9

iron nail, single cleavage plane, dark black, brown streak (mica fam)

Question 10

halite

Answer 10

iron nail, clear, white, or pink, waxed luster, 3 cleavage planes 90º,

Question 11

⭐️calcite

Answer 11

iron nail, glassy luster, 3 cleavage planes, rhombohedron, reacts to HCL

Question 12

serpentine

Answer 12

iron nail, green, opaque, smooth, rounded

Question 13

fluorite

Answer 13

iron nail, translucent many colors, 4 cleavage planes octahedral

Question 14

garnet

Answer 14

harder, 12 sided polygon, glassy gemstone-like luster

Question 15

olivine

Answer 15

harder, always green, glassy luster, tiny grains, transparent/lucent conchoidal fracture

Question 16

⭐️pyroxene

Answer 16

harder, dark gray/black, matte

Question 17

hornblende

Answer 17

harder, dark gray/black, glassy, splinter-like fractures

Question 18

⭐️plagioclase feldspar

Answer 18

harder, 2 cleavage planes 90º, twinning (thin bands look sliced)

Question 18

⭐️quartz

Answer 18

harder, glassy luster, any color, conchoidal fracture

Question 19

⭐️potassium feldspar

Answer 19

harder, 2 cleavage planes 90º, pink/white color