Kermesite
From Wikipedia, the free encyclopedia
| Kermesite | |
|---|---|
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| General | |
| Category | Mineral |
| Chemical formula | (Sb2S2O) |
| Identification | |
| Color | Red |
| Crystal habit | acicular fibrous radial |
| Crystal system | Triclinic |
| Cleavage | Perfect |
| Fracture | Brittle |
| Mohs Scale hardness | 1-1.5 |
| Luster | Adamantine |
| Pleochroism | None |
| Streak | Brownish red |
| Specific gravity | 4.5 - 4.8+ |
| Solubility | H2O insoluble |
Kermesite or antimony oxysulfide is also known as red antimony (Sb2S2O) . The name kermesite is a name derived from the Persian qurmizq, which later became "crimson" and was given to the mineral’s color which ranges from cherry red to a deep red bordering on black. Kermesite is the result of partial oxidation between stibnite (Sb2S3) and other antimony oxides such as valentinite (Sb2O3) or stibiconite (Sb3O6(OH)). Under certain conditions with oxygenated fluids the transformation of all sulfur to oxygen would occur but kermesite occurs when that transformation is halted.
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[edit] Mining and specimens
Deposits of this mineral have been found all over the world however notable deposits have been found in Saxony, Germany; Quebec and Nova Scotia, Canada; Sonora, Mexico and Algeria.
A few excellent specimens of kermesite are on display in museums. The Smithsonian displays a 7 by 7 cm sample from Zimbabwe, while the Geology Museum at the University of Wisconsin-Madison has a superb example of kermesite from the F John Barlow collection.
[edit] History and uses
Kermesite or red antimony has been used as early as the Old Kingdom’s 6th Dynasty in ancient Egypt (c.2345-2181 BCE) in lip cosmetics and in the 18th Dynasty Queen Hatshepsut (Maatkare) (1498-1483 BCE) negotiated with the land of Punt for it s colored antimony deposits. Besides stibnite which was used for eye liner red antimony is one of the oldest minerals used in cosmetics. Further archaeological evidence indicates that antimony levels were higher in ancient Egyptian female remains which had exposure to both antimony compounds (Bencze, 1994). Because of its color, the precipitate of kermesite was used as a coloring agent and in alchemy. Because of alchemy’s focus on material transformation as evidenced by color, red antimony was used to produce the red state. Kermesite is the mineral state for Kermes mineral which was used extensively in the medical field for centuries
Presently, kermesite is collected for the beauty of its crystal metallic structure and not used in either cosmetics or the medical field any longer due to the toxic affects that it shares with antimony; less harmful substitutes have been found using both organic and pharamceutical production.
[edit] References
[edit] Sources
- Bencze, Koloman. “Antimony” pp. 227-235. Handbook on Metals in Clinical and Analytical Chemistry (ed.) Hans G Seiler (1994) ISBN 0-8247-9094-4
- Sneader , Walter. Drug Discovery: A History (2005). ISBN 0-471-89980-1
