Geo- Mineral Properties and Identification

Sphalerite (ZnS)

-light brown streak
-sulfur smell

Galena (PbS)
-lead

-heavy palm weight
-cubic cleavage
-metallic dark grey streak

Gypsum
-sheet rock

-scratch with fingernail
-chalky white streak
-layered sheets of cleavage

Hematite (Fe2O3)
-iron = red

-metallic
-auburn streak

Halite (NaCl)
-salt

-90 degree cleavage
-white chalky streak

Graphite (C)

-messy
-pencil material

Flourite (CaF2)

-octahedral cleavage
-color from inside out
-varies colors

Magnetite (Fe3O4)

-magnetic

Kaolinite Clay

-extremely light palm-weight
-powdery material

Hematite (Fe2O3)
-iron = red

-red/orange streak
-earthy luster

Calcite (CaCO3)

-lacks 90 degree cleavage
-highly reactive to acid

Pyrite (FeS2)

-cubic cleavage
-"fools gold"

Quartz (SiO2)

-scratches glass
-no defined cleavage

Biotite

-flakes off
-1 cleavage set

Feldspar (Orthoclase)

-barely scratches glass
-salmon pink

Pyroxene (Augite)

-close to 90 degree cleavage
-no streak
-can be greenish

Olivine

-no cleavage
-olive green color

Talc

-soapy feeling
-pearly luster

Feldspar (Na- Plagioclase)
-white color = Na

-striations present
-no streak
-reflects light

Muscovite

-flaky
-1 cleavage set

Amphibole (Al2O3)

-tight planes
-unique light pattern

Feldspar (Ca- Plagioclase)
-deep black color = Ca

-striations on face
-no streak

Quartz (SiO2)

-scratches glass
-no cleavage

Garnet
-can be green

-dodecahedron
-no streak
-red undertone