Spessartine
Revision as of 06:42, 24 July 2013 by (username removed)
Description
A garnet composed of manganese aluminum silicate. The color of spessartine may range from an orange-yellow to brownish-red. Gem quality stones are mined in Germany, Malagasy Republic, India, and the United States (Colorado and Maine). Historically, spessartine gemstones are rare but a few have been found dating to the 2nd and 3rd century BCE (Odgen 1982).
Synonyms and Related Terms
garnet; spessartite; espesartina (Esp;); Spessartin (Deut.); spessartien (Ned.)
Other Properties
Fracture = conchoidal. Luster = vitreous to resinous. Streak = colorless.
| Composition | 3MnO-Al2O3-3SiO2 |
|---|---|
| Mohs Hardness | 7.0 - 7.5 |
| Density | 4.15 |
| Refractive Index | 1.800-1.810 |
Additional Information
° J. Ogden, Jewelry of the Ancient World, Rizzoli International Publications, New York, 1982.° Mineralogy Database: Spessartine
Comparisons
Properties of Common Gemstones
Authority
- G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 354
- Jack Odgen, Jewellery of the Ancient World, Rizzoli International Publications Inc., New York City, 1982
- Encyclopedia Britannica, http://www.britannica.com Comment: "spessartine." Encyclopædia Britannica. 20 Sept. 2005 .
- C.W.Chesterman, K.E.Lowe, Audubon Society Field Guide to North American Rocks and Minerals, Alfred A. Knopf, New York, 1979
- Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
- The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998