Guest Author - Susan Dorling

Once available primarily as dark, reddish brown stones, the gem marketplace now offers beautiful garnets in every color, except blue. From bright green drusy Uvarovite, to neon orange mandarin Spessartites, to pure spectral green Tsavorites and raspberry pink rhodolites, garnets are available in a wide price rnage and many cutting styles. With harnesses ranging from 6.5 to 7.5, depending on the species, garnets are reasonable durable gemstones for most jewelry uses. Main sources include India, Madagascar, Russia, Australia, Sri Lanka, and the USA. As there are no gem treatments commonly used on garnet to enhance its color or other properties, it generally is safe to assume the stones are natural.

Spessartite Garnet
Named for Spessat, in NW Bavaria, Germany, this orangey, lusrous garnet variety is not well known outside of gemological circles. Ranging from red to reddish orange to orange to orangey yellow to orangey brown this variety is the manganese aluminum silicate member of a solid solution series of garnets. In general, the less iron which is present in the crystal structure, the lighter and purer orange the color will be. With a higher refractive index and polish luster than most of the garnet group, a clean, well polished specimen of this variety is a delight to the eye. There are numerous deposits worldwide, but in today's market the Nigerian and Mambian stones command the highest prices and the greatest admiration. The Mamibian stones are the purest orange and have been given the trade name "Mandarin" by their promoter. As lovely as they are, the typical stone is under one carat and may be included. A recent find of gem quality Spessartite in Nigeria has provided the world with larger, cleaer stones that have just slightly less orangey purity than the Manibian pieces.

As with all garnets, there are essentially no simulants or enhancements in the market to worry about and they are relatively hardy gems for jewelry use. Little precaution needs to be exerted in setting and wearing these gems.

Value Considerations
As with most non-diamond gemstones, color is everything when it comes to setting price. In the case of Spessartites, purity of color, be it red-orange or orange, is the hallmark of quality. Lesser prices will be awarded to gems with more brown in their hue. As with many gems, larger pieces command a higher per carat price than smaller stones, and clarity is always an issue. The beauty of the cut is a secondary factor modifying price.

Gemological Properties
Makeup: Manganese aluminum silicate
Crystal System: cubic
Refractive Index: 1.79 - 1.81
Density: 4.1 - 4.2
Dispersion: .027
Polish Luster: vitreous to subadamantine
Cleavage: none
Fluorescence: inert
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Information about garnets courtesy of the Jewelry Collecting site's gemology expert, Barbara W. Smigel, PhD., Graduate Gemologist, GIA

Visit Artistic Colored Stones for more information about garnets, and to shop for quality one-of-a-kind gemstones, gemstone carvings, and beautiful designer jewelry.

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