Teruggite

Teruggite is a mineral with the chemical formula Ca4MgAs2B12O22(OH)12·12(H2O). It is colorless. Its crystals are monoclinic to prismatic. It is transparent. It is not radioactive. It has vitreous luster. Teruggite is rated 2.5 on the Mohs Scale of hardness.
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General Information:
 Chemical Formula:
Ca4MgAs2B12O22(OH)12·12(H2O)
 Composition:
(Molecular Weight = 1,236.44 gm)
Calcium 12.97 % Ca
Magnesium 1.97 % Mg
Boron 10.49 % B 
Arsenic 12.12 % As
Hydrogen 2.93 % H 
Oxygen 59.52 % O 
 Empirical Formula:
Ca4MgAs2B12O22(OH)12·12(H2O)
 IMA Status:
Approved IMA 1968
Physical Properties:
 Color:
colorless.
 Density:
2.149
 Diaphaniety:
Transparent
 Hardness:
2.5 - Finger Nail
 Luster:
Vitreous (Glassy)
 Streak:
white
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