Blue topaz

Blue Topaz

Description

A blue variety of Topaz used as a gemstone. Naturally occurring blue topaz is very rare. The blue color can be artificially 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.)

Physical and Chemical 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
Density	3.4-3.6 g/ml

Resources and Citations

• Encyclopedia Britannica, http://www.britannica.com
• Minerals.net at https://www.minerals.net/mineral/topaz.aspx
• Geology.com at https://geology.com/gemstones/blue-topaz/