General Information:
Chemical Formula:
K(Mg,Fe)6(Si,Al)8O20(OH)4·x(H2O)
Environment:
Found in a wide variety of sedimentary environments.
Locality:
Common world wide.
Name Origin:
Named for its relationship to biotite.
Physical Properties:
Cleavage:
[???] Perfect
Color:
golden yellow or black.
Diaphaniety:
Translucent
Hardness:
2.5-3 - Finger Nail-Calcite
Luster:
Sub Metallic
Streak:
white
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