Zoisite
| Zoisite | ||
|---|---|---|
Specific gravity 3.10–3.36 | | |
| Optical properties | biaxial positive | |
| Refractive index | nα = 1.696 – 1.700 nβ = 1.696 – 1.702 nγ = 1.702 – 1.718 | |
| Birefringence | 0.006–0.018 | |
| Pleochroism | X = pale pink to red-violet; Y = nearly colorless to bright pink or deep blue; Z = pale yellow to yellow-green | |
| References | [2][3][4] | |
| Major varieties | ||
| Tanzanite | Gem-quality zoisite, blue-purple | |
| Thulite | Pink | |
Zoisite, first known as saualpite, after its
sorosilicate belonging to the epidote group of minerals. Its chemical formula is Ca2Al3(SiO4)(Si2O7)O(OH
).
Zoisite occurs as
polymorph
of Ca2Al3(SiO4)(Si2O7)O(OH).
Transparent material is fashioned into gemstones while translucent-to-opaque material is usually carved.
The mineral was described by Abraham Gottlob Werner in 1805. He named it after the Carniolan naturalist Sigmund Zois, who sent him its specimens from Saualpe in Carinthia.[5] Zois realized that this was an unknown mineral when it was brought to him by a mineral dealer, presumed to be Simon Prešern, in 1797.[6]
Sources of zoisite include Tanzania (tanzanite), Kenya (anyolite), Norway (thulite), Switzerland, Austria, India, Pakistan, and the U.S. state of Washington.
See also
References
- S2CID 235729616.
- ^ http://rruff.geo.arizona.edu/doclib/hom/zoisite.pdf Handbook of Mineralogy
- ^ http://www.mindat.org/min-4430.html Mindat
- ^ http://webmineral.com/data/Zoisite.shtml Webmineral data
- ^ Flint-Rogers, Austin (1937). Introduction to the Study of Minerals. McGraw-Hill Book Company. p. 478.
- ISSN 0016-7789.
Bibliography
- Hurlbut, Cornelius S.; Klein, Cornelis, 1985, Manual of Mineralogy, 20th ed., ISBN 0-471-80580-7
- Faye, G. H.; Nickel, E. H. (1971). "On the pleochroism of vanadium-bearing zoisite from Tanzania" (PDF). The Canadian Mineralogist. 10: 812–821.
External links
Wikimedia Commons has media related to Zoisite.
- Chisholm, Hugh, ed. (1911). . Encyclopædia Britannica. Vol. 28 (11th ed.). Cambridge University Press. pp. 1000–1001.