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Glittering
Stones >> Semi
Precious Stones >> Spinel
Semi Precious Stone Spinel
Spinel is one of the groups of minerals that crystallize
in the isometric system with an octahedral habit, and
whose chemical compositions are also analogous. These minerals
are combinations of bivalent and trivalent oxides of magnesium,
zinc, iron, manganese, aluminum and also chromium, the general
formula being represented as R''O•R'''2O3. The bivalent
oxides may be MgO, ZnO, FeO and MnO, and the trivalent oxides
may be Al2O3, Fe2O3, Mn2O3 and Cr2O3.
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Historical Facts of Spinel
| Refractive Index |
1.712 - 1.762 |
| Chemical Composition |
MgAl2O4 |
| Hardness |
8 |
| Crystal habit |
Cubic, Octahedral |
| Crystal system |
Isometric |
| Density |
3.54 - 3.63 |
| Luster |
Vitreous |
| Occurrence |
Sri Lanka, Burma, Thailand, Australia, Kenya, Brazil
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| Types of spinel |
Gahnite, Franklinite, Ringwoodite, Magnetite, Ulvöspinel,
Hercynite, Jacobsite, Trevorite, Chromite |
| Color |
Orange, Pink, Black, Blue, Lavender, Mauve, Greenish
blue, Vivid red |
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Gem Jewelry Spinel
| Spinel Bracelet |
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| Spinel Earrings |
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| Spinel Necklace |
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| Spinel Rings |
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