Datolite

Transparent, colourless crystals of datolite are cut for collectors only. A tinge of yellow, green, or white may also be present. Datolite genrally occurs as a massive material, which may contain copper inclusions.

Localities include Austria, Italy, Norway, United States, Germany, and England. The primary source of massive datolite with inclusions is the Lake Superior area of North America.

Datolite Properties

Chemical Composition: 
Calcium hydroxyborosilicate
Crystal System / Forms: 
Monoclinic
Hardness: 
5
Specific Gravity: 
2.95
Lustre: 
Vitreous
Refractive Index / Birefringence: 
1.62-1.65 / 0.044
Geological Occurrence: 
Austria, Italy, Norway, United States, Germany, and England.
Cuts & Uses: 
Step cut