Enstatite
Mg2(Si2O6)
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Chemical name
Enstatite |
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Chemical formula
Mg2(Si2O6) |
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Crystal system
orthorhombic |
|
Crystal Class
Dipyramidal (mmm)
H-M symbol: (2/m 2/m 2/m) |
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Space Group
Pbca |
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Unit cell
a [Å]:18,23 b [Å]:8,84 c [Å]:5,19 |
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Molecular weight [g/mol]
100.387 |
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Formula units
Z = 8 |
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Twinning
Simple and lamellar on [100] |
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Mohs hardness
5 to 6 |
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Density [g/cm3]
3.2 - 3.9 |
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Fracture / Tenacity
Uneven, brittle |
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Color
White, grey, green, yellow or brown - colorless in thin section. |
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Streak
Gray |
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Luster
Vitreous, pearly on cleavage |
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Optical character
Biaxial (+) |
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Refractive Index
nα = 1.650–1.668; nβ = 1.652–1.673; nΥ = 1.659–1.679 |
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Birefringence δ
0.009–0.011 |
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Pleochroism δ
Pale green to pale orange |
