Keckite

General Information:
 Chemical Formula:
Ca(Mn,Zn)2Fe+++3(PO4)4(OH)3·2(H2O)
 IMA Status:
Approved IMA 1979
Physical Properties:
 Cleavage:
[001] Good, [100] Good
 Color:
brown, gray brown, or yellow brown.
 Density:
2.6
 Diaphaniety:
Transparent to Translucent
 Hardness:
4.5 - Between Fluorite and Apatite
 Luster:
Earthy (Dull)
 Streak:
yellow white
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