Harstigite

General Information:
 Chemical Formula:
Ca6MnBe4(SiO4)2(Si2O7)2(OH)2
 Composition:
(Molecular Weight = 885.97 gm)
Calcium 27.14 % Ca
Manganese 6.20 % Mn
Beryllium 4.07 % Be
Silicon 19.02 % Si
Hydrogen 0.23 % H 
Oxygen 43.34 % O 
 Empirical Formula:
Ca6Mn2+Be4(SiO4)2(Si2O7)2(OH)2
 Environment:
Occurs with garnet and rhodonite.
 Locality:
Harstig mine, Pajsberg, near Persber, Vermland, Switzerland.
 Name Origin:
Named after its locality.
Physical Properties:
 Cleavage:
None
 Color:
colorless or white.
 Density:
3.16
 Diaphaniety:
Translucent
 Habits:
Crystalline - Fine - Occurs as well-formed fine sized crystals., Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).,
 Hardness:
5.5 - Knife Blade
 Luster:
Vitreous (Glassy)
 Streak:
white
More details...