General Information:
Chemical Formula:
(Mn,Ca,Mg)4(Al,Mn,Fe,Mg)6(As,V,P,Si)(O,OH)4(SiO4)2Si3O10(OH,
Locality:
Salmchateau in the Ardennes Mountains, Belgium.
Name Origin:
After the locality.
Physical Properties:
Cleavage:
[010] Perfect, [110] Distinct
Color:
yellow, yellow brown, dark brown, orange, or black.
Density:
3.62
Habits:
Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline)., Euhedral Crystals - Occurs as well-formed crystals showing good external form.,
Hardness:
6-7 - Orthoclase-Quartz
Luster:
Subadamantine
Streak:
pale brownish yellow
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