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Glittering
Stones >> Semi
Precious Stones >> Calcite
Semi Precious Stone Calcite
Calcite is a carbonate mineral and the most stable polymorph
of calcium carbonate (CaCO3). The other polymorphs in calcite
are the minerals aragonite and vaterite. The aragonite will change
to calcite at 470°C, and vaterite is even less stable.
Calcite seas existed in Earth history when the primary inorganic
precipitate of calcium carbonate in marine waters was low-magnesium
calcite that opposed to the aragonite and high-magnesium calcite
precipitated.
The mineral Calcite primarily often constituent of the shells
of marine organisms, e.g., plankton (such as coccoliths and planktic
foraminifera), the hard parts of red algae, some sponges, brachiopoda,
echinoderms, most bryozoa, and parts of the shells of some bivalves,
such as oysters and rudists).
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Historical Facts of Ammolite
| Refractive Index |
1.640 - 1.660, 1.486 |
| Chemical Composition |
CaCO3 |
| Hardness |
3 |
| Density |
2.71 |
| Crystal Group |
Trigonal Hexagonal Scalenohedral |
| Luster |
Vitreous |
| Occurrence |
New Mexico |
| Color |
Colorless, White, Gray, Yellow, Green, Pink |
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Gem Jewelry Bloodstone
| Calcite Bracelet |
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| Calcite Earrings |
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| Calcite Necklace |
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| Calcite Rings |
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