By Didier Descouens (Own work) [GFDL or CC-BY-SA-3.0-2.5-2.0-1.0], via Wikimedia Commons
An overview on Pyrrhotite Jewelry and Gemstones. Covers details and essential information on the physical properties and characteristics of Pyrrhotite gems.
Pyrrhotite Information
| Data | Value |
|---|---|
| Name | Pyrrhotite |
| Stone Sizes | Cabochons of almost any size could be cut from the massive material. Such stones are always opaque and metallic and can be attractive. |
| Formula | Fe1-xS. |
| Colors | Bronze-yellow to bronze-red or brownish; tarnishes readily, becomes iridescent. |
| Fracture | Subconchoidal to uneven, Sometimes basal parting observed |
| Hardness | 3.5-4.5 |
| Cleavage | None |
| Crystallography | Hexagonal; also orthorhombic, monoclinic, depending on stoichiometry. Crystals tabular, platy, pyramidal, sometimes in clusters (rosettes); usually massive or granular. |
| Birefringence | None |
| Luster | Metallic. |
| Specific Gravity | 4.58-4.65 |
| Transparency | Opaque. |
Also known as pyrrohotite.
Streak: grayish black.
Other Tests: Magnetic, varying in intensity, lost on heating. Decomposed by HCl.
Occurrence: Associated with pyrite and other sulfides throughout the world, often as a magmatic segregation in basic igneous rocks. Occasionally in pegmatites and contact metamorphic rocks, fumaroles, and basalts. Also occurs in meteorites.
Sudbury, Ontario, Canada.
Morro Velho, Brazil.
Rumania; Italy; Germany; Norway; Sweden.
Potosi Mine, Santa Eulalia, Chihuahua, Mexico.
Pennsylvania; Tennessee; New York; Maine; Connecticut.
Name: From a Greek word meaning reddish.
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