Geology 1250 quiz 1

Halite

silicate- no nonmetallic 3 cleavage planes- 90 degrees softer than glass other- clear, white streak

Calcite

silicate- no nonmetallic 3 cleavage planes- not 90 degrees softer than glass other- clear/black, white streak

Biotite

silicate- yes nonmetallic 1 cleavage plane softer than glass other- thin, black/gold, no streak

Amphibole (Hornblende)

silicate- yes nonmetallic 2 cleavage plans- not 90 degrees harder than glass other- black, shiny, grey streak

Olivine

silicate- yes nonmetallic no cleavage planes harder than glass other- rough, yellow/green, white streak

Quartz

silicate- yes nonmetallic no cleavage planes- crystal faces harder than glass other- crystal faces, pink/clear, white streak

Muscovite

silicate- yes nonmetallic 1 cleavage plane softer than glass other- thin, clear, no streak

Plagioclase (Albite)

silicate- yes nonmetallic 2 cleavage plans- 90 degrees harder than glass other- shimmer, white&grey, white streak

Gypsum

silicate- yes nonmetallic nonmetallic 1 cleavage plane softer than glass other- clear, white streak, thin but not paper thin

Pyroxene

Shape: Orthorhombic or monoclinic Luster: Glassy or metallic Color: Black Streak: White, light green or light brown Hardness: 5-6.5 on Mohs Hardness Scale Cleavage: Two planes that meet at nearly a 90-degree angle Fracture: Most have uneven and brittle fractures.

K-feldspar

KalSi308 - Potassium Aluminum Silicate Color - Typically off-white or shades of red, orange and brown, occasionally green. Cleavage - One perfect cleavage and one good cleavage that meet at nearly 90° Hardness - 6 (harder than glass) Specific Gravity - 2.6 LusterCrystals are vitreous (glass-like) to porcelaneous (porcelain-like) Streak - white

Gold

gold color, no cleavage, no distinct shape