Uvarovite | |
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General | |
Category | Nesosilicate |
Formula (repeating unit) | Ca3Cr2Si3O12 |
IMA symbol | Uv[1] |
Strunz classification | 9.AD.25 |
Crystal system | Cubic |
Crystal class | Hexoctahedral (m3m) H-M symbol: (4/m 3 2/m) |
Space group | Ia3d |
Unit cell | a = 11.99 Å; Z = 8 |
Identification | |
Color | Green, emerald-green, green-black |
Crystal habit | Euhedral crystals, granular, massive |
Fracture | Uneven, conchoidal |
Mohs scale hardness | 6.5–7.5 |
Luster | Vitreous |
Streak | White |
Diaphaneity | Transparent, translucent |
Specific gravity | 3.77–3.81 |
Optical properties | Isotropic |
Refractive index | n = 1.865 |
Other characteristics | Fluorescent red in both short and long UV |
References | [2][3][4] |
Uvarovite is a chromium-bearing garnet group species with the formula: Ca3Cr2(SiO4)3. It was discovered in 1832 by Germain Henri Hess who named it after Count Sergei Uvarov (1765–1855), a Russian statesman and amateur mineral collector.[2] It is classified in the ugrandite group alongside the other calcium-bearing garnets andradite and grossular.[5]
Uvarovite is the rarest of the common members of the garnet group,[6] and is the only consistently green garnet species, with an emerald-green color. It occurs as well-formed fine-sized crystals.