Hardness

scratching substance of known hardness with mineral of unknown hardness 

Fingernail 2.5

Copper Penny 3.5

Wire Pick 4.5

Glass plate 5.5

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Quartzite

sugary

medium grain size

Scratches glas

oily luster

Hematite

2.5 Hardness

Earthy luster (redish)

leaves red brown streak

2d cleavage

Pyrite

metalic luster

grows in cubes

streak is gray

hardness is 6 scratches glass

"fools gold"

Muscovite Mica

Hardess is 2 fingernail scratches it

transparent thin sheets

1 cleavage

brown or red brown

Biotite Mica

fingernail scratches it

opaque black in color

breaks into thin sheets

Gypsum

hardness 2

breaks into sheets

rhombus

transparent to opaque

Talc

opaque 

greasy soapy feel

scratches off into powder

Plagioclase Feldspar

Hardness 6 Scratches glass

breaks along 2 planes at 90 degrees

striations on cleavage surface

white or gray

K-Feldspar

Breaks along 2 cleavage plains at about 90 degrees

muscle fibers run along cleavage plain

orange, brown, pink

Amphibole
black color

breaks along 2 cleavage plains at 60 degrees and 120 degrees

splintery cleavage

gray/green streak 

Calcite

hardess 3

Breaks aling 3 clevage plains

rhombic shape

reacts to HCL

colorless, white, yellow

Galena

Hardness 2.5

verry dense 

breaks along 3 clevage plains making a cube

metalic luster

bright silvery gray

Halite (rock salt) 

hardness 2.5

Breaks along 3 clevage plains, cube

opaque

colorless, yellow, or brown