Fenaksite

General Information:
 Chemical Formula:
(K,Na,Ca)4(Fe++,Fe+++,Mn)2Si8O20(OH,F)
 IMA Status:
Approved IMA 1959
Physical Properties:
 Cleavage:
[100] Good, [010] Good
 Color:
brown or light pink.
 Density:
2.744
 Hardness:
5-5.5 - Apatite-Knife Blade
 Luster:
Pearly
 Streak:
white
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