Artinite

Artinite
Artinite – Atlas mine, San Benito, California, US
Artinite from New Idria District, California
General
CategoryCarbonate mineral
Formula
(repeating unit)
Mg2(CO3)(OH)2·3H2O
IMA symbolArt[1]
Strunz classification5.DA.10
Crystal systemMonoclinic
Crystal classPrismatic (2/m)
(same H-M symbol)
Space groupC2/m
Unit cella = 16.56, b = 3.15
c = 6.22 [Å]; β = 99.15°; Z = 2
Identification
ColorWhite
Crystal habitAcicular crystals, fibrous veinlets, botryoidal crusts, and spherical aggregates
CleavageOn {100} perfect; on {001} good.
Mohs scale hardness2.5
LusterVitreous, silky
StreakWhite
DiaphaneityTransparent
Specific gravity2.01 – 2.03
Optical propertiesBiaxial (−)
Refractive indexnα = 1.488 – 1.489 nβ = 1.533 – 1.534 nγ = 1.556 – 1.557
Birefringenceδ = 0.068
References[2][3][4]

Artinite is a hydrated basic 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.[2]

It was first reported in 1902 in Lombardy, Italy. It was named for Italian mineralogist, Ettore Artini (1866–1928).[3]

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.
  1. ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
  2. ^ a b Handbook of Mineralogy
  3. ^ a b Artinite on Mindat.org
  4. ^ Artinite on Webmineral