Click here to Search and buy pyro-spessartite garnet

---
General information

Pyro-spessartites are difficult to define or pin down. They are, by definition, a mixture between pyrope and spessartine garnets but in East Africa, molecules of other members of the garnet family, almandine garnets in particular, are usually also present in small quantities, and these lesser constituents affect the properties of the gems in various ways. The stones we stock come from the valley of the Umba River, near the coast on the Tanzanian side of the Kenya-Tanzania border. This locality is world famous for its "Umbalite garnets", many of which are pyro-spessartites (including the color change garnets, for which, see:
First color-change garnet to have been discovered

Because some of these garnets contain a greater percentage of pyrope molecules than others, and others are richer in the spessartine molecule, pyro-spessartites exhibit gems with a very broad range of characteristics. The illustration on this page is a plot which shows how the color may vary despite the strong correlation of Refractive Index to Specific Gravity. Some of these stones exhibit a color shift which depends on the light source, and our picture would not have been quite the same if it had been taken under different lighting conditions. Umbalites are usually small; rarely above five carats when cut. We've sold some lovely pieces and as can be deduced from the illustration, each pyro-spessartite is truly unique. This is in stark contrast with the classic Bohemian garnets, which are pyropes and which resemble one another like peas in a pod.

Chemistry:
System:
Hardness:
Density:
Ref. Index:
Birefringence:
Pleochroism:

On the Internet:
View Spessartite information at www.mindat.org
First color-change garnet to have been discovered

Copyright © 2005-2010 Swala Gem Traders. All rights reserved.