Mineral & Rock Exam 1

Front 1

Chlorite

Back 1

Hardness: 1-2
Streak: Green
Color: Green
Luster: Satiny
Other: Flaky

Front 2

Graphite

Back 2

Hardness: 1-2
Streak: Black
Color: Black
Luster: Metallic
Other: Splits into thin flexible sheets
- used for making lead

Front 3

Bauxite

Back 3

Hardness: 1-3
Streak: Yellow~Brown
Color: Yellow, White, Brown
Luster: Dull
Other: English-pea shaped masses, rounded
- used for an aluminum ore

Front 4

Galena

Back 4

Hardness: 2.5
Streak: Lead Grey
Color: Grey
Luster: Metallic
Other: Heavy Cubic Cleavage
- used as an ore of lead

Front 5

Azurite

Back 5

Hardness: 3.5
Streak: Blue
Color: Blue
Luster: Dull
Other: Rounded, dull massive
- used as an ore of copper

Front 6

Malachite

Back 6

Hardness: 3.5-4
Streak: Green
Color: Green
Luster: Dull, velvety, silky
- used as an ore of copper
Other: May be fibrous, laminated, or nodular

Front 7

Chalcopyrite

Back 7

Hardness: 3.5-4
Streak: Greenish~black
Color: Brassy yellow
Luster: Metallic
Other: Tarnished to bronze to purple
- used as an ore of copper

Front 8

Sphalerite

Back 8

Hardness: 4
Streak: Yellow
Color: White, Yellow brown
Luster: Resinous
Other: HCI on powder give H2S rotten egg smell
- used as an ore of zinc

Front 9

Limonite

Back 9

Hardness: 3.5-5
Streak: Yellow brown
Color: Yellow, brown
Luster: Dull
Other: Often sandy, causing error in hardness, rusty color
- used as an ore of iron

Front 10

Hornblende

Back 10

Hardness: 5.5
Streak: Pale grey~green
Color: Greenish~black
Luster: Dull to glassy
Other: 2 directions of cleavage, woody or blocky appearance

Front 11

Magnetite

Back 11

Hardness: 6
Streak: Black
Color: Black
Luster: Metallic
Other: Magnetic heavy
- as an ore of iron

Front 12

Hematite

Back 12

Hardness: 6
Streak: Reddish~brown
Color: Red, Grey, Green
Luster: Dull, greasy, or metallic
Other: May be oolitic, may be flaky, may contain sand
- used as an ore of iron

Front 13

Pyrite

Back 13

Hardness: 6.5
Streak: Greenish~black
Color: Brassy Yellow
Luster: Metallic
Other: Crystal faces may be striated

Front 14

Talc

Back 14

Hardness: 1-2
Color: White to blue~green
Luster: Greasy
Other: Soapy feel
- Used to make powder, chalk

Front 15

Kaolin

Back 15

Hardness: 1-2
Color: White
Luster: Dull
Other: Fine aggregate, earthly smell when damp
- used to make pottery

Front 16

Gypsum

Back 16

Hardness: 2
Color: White to Clear
Luster: Dull Glassy
Other: Fine aggregate, or fibrous or in cleavage blocks
- used to make sheetrock

Front 17

Muscovite Mica

Back 17

Hardness: 2.5
Color: Clear
Luster: Glassy
Other: Good cleavage in 1 direction, splits into thin, flexible sheets
- used for making paint

Front 18

Biotite Mica

Back 18

Hardness: 2.5
Color: Black
Luster: Glassy
Other: Good cleavage in 1 direction, splits into thin, flexible sheets
- used for making paint

Front 19

Halite

Back 19

Hardness: 2.5
Color: Varies, often clear
Luster: Glassy
Other: Salty taste, damp feel, cubic cleavage
- used for table salt

Front 20

Calcite

Back 20

Hardness: 3
Color: Varies
Luster: Glassy
Other: effervesces easily with HCI, cleavage in 3 directions
- used for making cement

Front 21

Fluorite

Back 21

Hardness: 4
Color: Varies
Luster: Glassy
Other: Often shows 4 directions of cleavage

Front 22

Feldspar (Pink & White)

Back 22

Hardness: 6
Color: Varies
Luster: Glassy
Other: 2 directional cleavage may have porcelain appearance
- used for a glaze on china

Front 23

Olivine

Back 23

Hardness: 6.5
Color: Yellowish~green
Luster: Glassy
Other: Usually olive-green color

Front 24

Garnet

Back 24

Hardness: 7
Color: Brownish~red
Luster: Glassy
Other: Often single crystals splotchy
- used as an abrasive

Front 25

Quartz

Back 25

Hardness: 7
Color: Varies
Luster: Glassy
Other: Conchoidal fracture, no cleavage
- used for making glass

Front 26

Corundum

Back 26

Hardness: 9
Color: Brown
Luster: Glassy to dull
Other: Often to hexagonal crystals, scratches quartz
- used as an abrasive

Front 27

Chert

Back 27

Hardness: 7
Color: Varies, often light
Luster: Dull
Other: Color varies, mircocyustalline variety