Chemistry: Hydrated carbonate, hydroxide of magnesium and chromium (an alteration product of chrome serpentine)
Crystal system: Trigonal; massive/aggregates.
Color: Purple, purplish red, lilac; may be veined with green serpentine.
Hardness: 1.5 -2
Cleavage: Perfect: basal; fracture: splintery.
Specific gravity: 2.15 – 2.22
Refractive index: 1.53 mean; Uniaxial negative.
Luster: Greasy or waxy.
Dispersion: -
Dichroism: Dark red to light red.
Occurrence: In serpentine rocks associated with chromite; Algeria, South Africa, Tasmania, Canada.
Notes
Decomposition product of chrome serpentine, veined with green; occasionally cut for collectors; distinct chrome spectrum – 3 bands in red between 635 – 630nm; cabochon, beads.
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