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
More details...