Class: Silicates
Group: Epidote
Original description: ‘Кlinozoisit’ Weinschenk, E., 1896. Ueber Epidot und Zoisit — Zeitschrift für Kristallographie 26: 166—169 [
view in ‘Library’].
Type locality: Gösleswand, Prägraten, Tyrol, Austria.
Type material: unknown.
Etymology: named for its monoclinic crystallography and the relationship to zoisite.
Distribution: Austria: Gösleswand, near Prägraten, Tyrol; Canada: from Timmins, Ontario; Czech Republic; Madagascar; Mexico; Norway: Arendal (
Anthony et al., 2001—2005).
Chemistry
Ca2Al3(SiO4)3(OH)
Essential elements: hydrogen (H), oxygen (O), aluminium (Al), silicon (Si), calcium (Ca).
Crystal data
Crystallography: monoclinic — prismatic.
Crystal habit: crystals prismatic, typically elongated and striated; commonly coarse to fine granular; also fibrous.
Twinning: lamellar on {100}, uncommon (
Anthony et al., 2001—2005).
Optical properties
Colour: colourless, pale yellow, pink, red, grey, green; colourless in thin section (
Anthony et al., 2001—2005).
Diaphaneity: transparent to translucent (
Anthony et al., 2001—2005).
Lustre: vitreous.
Refractive index: 1.67—1.734 — anisotropic [biaxial (+)] (
Lazzarelli, 2012).
Birefringence: 0.005—0.015.
Dispersion: no data.
Pleochroism: none.
Material from ‘Repository’
1 specimen: 0047 — 0.57 ct, Pakistan, Gilgit-Baltistan (Northern Areas), Baltistan, Skardu District, 35.3°N 75.61667°E.
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