Magnesium Iron Silicate
(Mg,Fe)2SiO4
|
Chemical name
Magnesium Iron Silicate |
|
Mineral name
Olivine |
|
Chemical formula
(Mg,Fe)2SiO4 |
|
Melting point [°C]
1800 |
|
Crystal system
orthorhombic |
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Crystal Class
orthorhombic-dipyramidal (2/m 2/m 2/m) |
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Space Group
Pbnm |
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Unit cell
a [Å]:6.01 b [Å]:4.78 c [Å]:10.30 |
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Molecular weight [g/mol]
153.31 |
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Formula units
Z=4 |
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Frequent crystal surfaces
{110}, {120} combinated with {021}, {101}, {111} and {010} |
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Mohs hardness
6.5 - 7 |
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Density [g/cm3]
3.2 - 4.4 |
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Cleavage
good on {001}, clear on {010} |
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Fracture / Tenacity
brittle to conchoidal |
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Color
yellow to yellow-green |
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Streak
white |
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Transparency
transparent to translucent |
|
Luster
vitreous |
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Optical character
biaxial (+) |
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Refractive Index
nα=~1.640; nβ=~1.660; nΥ=~1.680 |
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Birefringence δ
0.040 |
