Jimthompsonite

General Information:
 Chemical Formula:
(Mg,Fe++)5Si6O16(OH)2
 Composition:
(Molecular Weight = 619.47 gm)
Magnesium 14.71 % Mg
Iron 11.27 % Fe
Silicon 27.20 % Si
Hydrogen 0.33 % H 
Oxygen 46.49 % O 
 Empirical Formula:
Mg3.75Fe2+1.25Si6O16(OH)2
 IMA Status:
Approved IMA 1977
Physical Properties:
 Cleavage:
[210] Perfect
 Color:
colorless or pink brown.
 Density:
3.03
 Diaphaniety:
Transparent
 Hardness:
2-2.5 - Gypsum-Finger Nail
 Luster:
Silky - Pearly
 Streak:
white
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