Artinite

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Artinite
Artinite 2 on serpentine w- hydromagnesite Basic magnesium carbonate Mistake Mine Fresno County California 2175.jpg
Artinite, Mistake Mine, Fresno County, California (unknown scale)
General
Category Carbonate mineral
Formula
(repeating unit)
Mg2(OH)2CO3·3H2O
Strunz classification 05.DA.10
Crystal symmetry Monoclinic Space group: C 2/m
Unit cell a = 16.56 Å, b = 3.15 Å, c = 6.22 Å; β = 99.15°; Z=1
Identification
Color White
Crystal habit Acicular crystals, fibrous veinlets, botyroidal crusts, and spherical aggregates
Crystal system Monoclinic
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 USA. Size: 9.2 x 5.2 x 1.5 cm.

References[edit]