Bromellite

Bromellite
General
Category Oxide minerals
Formula
(repeating unit)		 BeO
(beryllium oxide)
Strunz classification 04.AB.20
Crystal system Hexagonal
Identification
Color White, colorless
Crystal habit prismatic
Cleavage [1010] Distinct
Mohs scale hardness 9
Luster Vitreous
Streak White
Diaphaneity Transparent to translucent
Specific gravity 3.02
Refractive index 1.719, 1.733
Pleochroism None
Melting point 2570°C

Bromellite, whose name derives from the Swedish chemist Magnus von Bromell (1670–1731), is a white oxide mineral, found in complex pegmatitic manganese-iron deposits, but is more frequently made synthetically. This is a rare mineral to encounter in its natural state, but it has been made synthetically for over 40 years.

Uses of bromellite

Bromellite, as a beryllium-containing mineral, has some uses. Industrially, natural specimens have the potential to be an ore of beryllium. It is one of the reagents that can be used in the manufacture of artificial emeralds. As an additive, bromellite confers high mechanical strength and very high thermal conductivity. In nuclear reactors, it is used as a moderator for fast neutrons. Ceramics containing bromellite are used in electronics, as well as crucibles for the melting of uranium and thorium. Bromellite, both natural and synthetic, is also used as a gemstone or as a collector's mineral. As a gemstone bromellite is extremely rare. To date there has been found only one crystal that is large enough to be cut. In 2000 Dunil Palitha Gunasekara of Ratnapura, Sri Lanka purchased a rough colorless 17.77-ct crystal from Ratnapura. He cut it into 15 pieces, of which 3 pieces with 2.80, 1.92 and 0.68 ct were sent to the GIA laboratory for further testing, since he thought them to be johachiodolite at first. These gemstones are the first reported examples of faceted gem-quality bromellite.

References

This article is issued from Wikipedia - version of the Sunday, March 06, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.