Characteristics of Danburite:

Chemical Name: Calcium boron silicate

Formula: CaB₂(SiO₄)₂

Colors: Colorless, yellow, pink, yellow-brown

Structure: Orthorhombic

Hardness: 7-7.5

Specific Gravity: 3

Refractive Index: 1.63-1.64

Lustre: Vitreous to greasy

Streak: White

Locations: Switzerland, Russia, Myanmar, Slovakia, USA, Mexico, Madagascar

What is Danburite? 

Danburite crystals are glassy prisms that resemble topaz, but in roughs they are distinguishable by their poor cleavage.  Danburite is name after the city of Danbury, Connecticut, USA, where it was first discovered as a distinct species in 1839. Danburite is cut as a gemstone, both faceted and en cabochon but is generally considered a collector’s stone. Large gem Danburites have ben found in Dalnegorsk, Russia in crystals up to 30cm long.