Taafeite Value, Price, and Jewelry Information
Taaffeite reacts to most gemological tests like mauve-colored spinel, but can be distinguished on the basis of its birefringence. Additional…
Nepheline Value, Price, and Jewelry Information
A variety called elaeolite is red, green, brown, or gray, massive or in crystals filled with minute inclusions. These inclusions produce…
Kornerupine Value, Price, and Jewelry Information
Star kornerupine also has been found (Mogok, Myanmar) but is very rare. Kornerupine is generally dark brown or green and not very attractive…
Enstatite Value, Price, and Jewelry Information
Most gem enstatites have indices in the range 1.663-1.673. The brown and green gems from Tanzania are enstatites, as are the brownish-green stones…
Dumortierite Value, Price, and Jewelry Information
Dumortierite is a beautiful and very hard material, eminently suitable for jewelry. The cabochon material is the only generally known form, since…
Cancrinite Value, Price, and Jewelry Information
Cancrinite is one of the most attractive of all opaque or translucent gem materials. It is a bit too soft for average wear, but its distinctive color…
Calcite Value, Price, and Jewelry Information
Calcite is common and abundant throughout the world. The material has little intrinsic value since it is not scarce. However, calcite is one of…
Cordierite Value, Price, and Jewelry Information
The crystal structure of cordierite has many similarities to that of beryl; indialite, the dimorph, in fact has the same structure as beryl. Iolite…
Beryl Value, Price, and Jewelry Information
The beryls are among the most popular, and also the most expensive, of all gems. A wide range of color is represented, from colorless to black. Beryls…
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