Artinite
| Artinite | |
|---|---|
|
Artinite from New Idria District, California | |
| General | |
| Category | Carbonate mineral |
| Formula (repeating unit) | Mg2(OH)2CO3·3H2O |
| Strunz classification | 5.DA.10 |
| Crystal system | Monoclinic |
| Crystal class |
Prismatic (2/m) H-M symbol: (2/m) |
| Space group | C2/m |
| Unit cell |
a = 16.56, b = 3.15 c = 6.22 [Å]; β = 99.15°; Z = 2 |
| Identification | |
| Color | White |
| Crystal habit | Acicular crystals, fibrous veinlets, botyroidal crusts, and spherical aggregates |
| Cleavage | On {100} perfect; on {001} good. |
| Mohs scale hardness | 2.5 |
| Luster | Vitreous, silky |
| Streak | White |
| Diaphaneity | Transparent |
| Specific gravity | 2.01 - 2.03 |
| Optical properties | Biaxial (-) |
| Refractive index | nα = 1.488 - 1.489 nβ = 1.533 - 1.534 nγ = 1.556 - 1.557 |
| Birefringence | δ = 0.068 |
| References | [1][2][3] |
Artinite is a hydrated magnesium carbonate mineral with formula: Mg2(CO3)(OH)2·3H2O. It forms white silky monoclinic prismatic crystals that are often in radial arrays or encrustations. It has a Mohs hardness of 2.5 and a specific gravity of 2.
It occurs in low-temperature hydrothermal veins and in serpentinized ultramafic rocks. Associated minerals include brucite, hydromagnesite, pyroaurite, chrysotile, aragonite, calcite, dolomite and magnesite.[1]
It was first reported in 1902 in Lombardy, Italy. It was named for Italian mineralogist, Ettore Artini (1866–1928).[2]
Artinite sometimes forms balls of radiating, fibrous crystals. Specimen from New Idria district, California US. Size: 9.2 x 5.2 x 1.5 cm.
References
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