In the large and varied garnet family of gemstones, there are six common varieties that are recognized based on their chemical composition. pyrope, almandine, spessartite, grossularite, uvarovite and andradite. There are also some mixed members, such as rhodolite garnet, which is a mixture of pyrope and almandite by composition.
New hybrid garnets continue to be discovered. In 1994 a mixture of grossular and andradite garnet was discovered in the West African country of Mali, and was named Mali Garnet. This discovery drew considerable interest because the grossular and andradite varieties are among the rarest and most valuable garnets. Members of the grossular group include tsavorite and hessonite. The most famous member of the andradite group is the rare demantoid garnet.
GARNET
The chemical composition of this new garnet is a mix of grossular (calcium aluminum silicate) and andradite (calcium iron silicate). Though Mali Garnets are predominantly grossularite, the presence of andradite lends mali an impressive dispersion or fire that is reminiscent of the diamond-like demantoid.
Most Mali Garnet is mined from alluvial deposits. When the first discovery was first made there a good supply of material on the market and prices were moderate. In recent years the supply has diminished and prices have risen, though Mali is still less expensive than the rare demantoid garnet. Large sizes are quite rare, so the price per carat tends to increase significantly for larger stones.
Colors range from yellow, to greenish yellow, to yellowish green, yellowish brown, to brown. Cut stones are valued for their brilliance and especially their dispersion when the body color is light enough to display good fire. No enhancements of this gemstone are currently known in the market.
The most valuable mali garnet color is the very rare chrome green. In general, yellow, greenish yellow and yellowish green stones sell for higher prices than the brownish stones. As with any gem, size, clarity and cut can affect the value significantly, with dispersion being a special value factor for Mali garnets.
Mali Garnet Gemstones GARNET
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