Janhaugite

General Information:
 Chemical Formula:
(Na,Ca)3(Mn++,Fe++)3(Ti++++,Zr,Nb)2(Si2O7)2O2(OH,F)2
Physical Properties:
 Cleavage:
[010] Distinct
 Color:
reddish brown.
 Density:
3.6
 Hardness:
5 - Apatite
 Luster:
Vitreous (Glassy)
 Streak:
light brown
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