Blue topaz
Description
A blue variety of Topaz used as a gemstone. Naturally occurring blue topaz is very rare. The blue color can be artificailly induced in clear topaz crystals by irradiation followed by heat. Blue topaz has often been confused with Aquamarine.
Synonyms and Related Terms
topaze bleue (Fr.); topázio azul (Port.)
Other Properties
Orthorhombic system with mostly prismatic crystals. Perfect cleavage in one direction.
Fracture = subconchoidal and uneven. Luster = vitreous. Streak = colorless to white.
Yellow topaz turns a soft red when heated.
Mohs Hardness | 8.0 |
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Density | 3.4-3.6 |
Authority
- Encyclopedia Britannica, http://www.britannica.com