Ore_Minerals.doc
9/23/2001
Use streak test for ore minerals
graphite· C
· soft
· light weight
· greasy
· dark
galena
· PbS
· heavy
· good cubic cleavage
· black to silver
hematite
· Fe2O3
· specular (#3), earthy (#10)
· sometimes a little magnetic
· read-brown streak
· red to silvery gray
magnetite
· Fe3O4
· magnetic
· black streak
· metallic luster; black
limonite
· Fe2O3۰H2O
· soft
· yellow-brown streak
sulfur
· S
· might smell of sulfur
· yellow-brown streak
· yellow
azurite
· Cu3CO3(OH)2
· blue
malachite
· Cu2CO3(OH)2
· green
pyrite
· FeS2
· harder than steel
· good cubes
· environment possible for gold deposition
· black streak
· brassy to golden yellow
chalcopyrite
· CuFeS2
· softer than steel
· metallic luster; little greenish gold
sphalerite
· ZnS
· good cleavage in many directions
· sulfur smell
· pale yellow streak
· luster
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