Chemistry: Calcium potassium silicate with hydroxyl and fluorite.
Crystal system: Rock; massive.
Color: Semi-translucent to opaque; various shades of purple (Mn and / or Fe); may be solid color, banded, streaky purple and white, or fibrous (possibly containing black, gray or brownish orange areas).
Hardness: 5 - 6
Cleavage: None; Fracture: splintery to granular.
Specific gravity: 2.68
Refractive index: 1.55 (mean).
Luster: Vitreous, if well polished.
Dispersion: -
Dichroism: -
Occurrence: Siberia (Russia), NW of Alden.
Notes
Decorative ornamental material (distinctive structure); discovered in 1976 along the Charo River, northeast of Lake Baikal; purplish rock may contain radiating greenish black needles of Agirine augite (a pyroxene); yellowish to orangy prismatic crystals (Tipaskite); whitish green patches of microcline feldspar and other minerals; flouorescence: inert but feldspar may glow dull red; beads, carvings.
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