Red beryl

Red beryl
General
CategoryCyclosilicate beryl
Formula
(repeating unit)
Be
3
Al
2
Si
6
O
18
with a mix of Mn3+
ions
Crystal systemHexagonal
Space groupP6/mcc
Identification
ColorDark red
TwinningExtremely rare
CleavageIndistinct
FractureConchoidal
Mohs scale hardness7.5–8
LusterVitreous
Streakwhite
Specific gravity2.66–2.87
Optical propertiesUniaxial (−)
Refractive index1.560–1.577
Birefringenceδ = 0.0040–0.0080
Dispersion0.014
Ultraviolet fluorescenceNone

Red beryl, formerly known as bixbite and marketed as red emerald or scarlet emerald, is an extremely rare variety of beryl as well as one of the rarest minerals on Earth.[1][2]: 19  The gem gets its red color from manganese ions embedded inside of beryllium aluminium cyclosilicate crystals.[1] The color of red beryl is stable up to 1,000 °C (1,830 °F). Red beryl can come in various tints like strawberry, bright ruby, cherry, and orange.[3]

The largest crystals of red beryl are about 2 cm (0.79 in) wide and 5 cm (2.0 in) long. However, most crystals are under 1 cm (0.39 in) long.[1] Recently,[when?] the red variety of pezzottaite has been sold in markets as red beryl by some sellers.[4]

  1. ^ a b c "Red Beryl: One of the World's rarest gemstones – mined in Utah". geology.com. Retrieved 2021-08-30.
  2. ^ Grande, Lance; Augustyn, Allison (2009-11-15). Gems and Gemstones: Timeless Natural Beauty of the Mineral World. University of Chicago Press. ISBN 978-0-226-30511-0.
  3. ^ "Red Beryl gemstone information". www.gemdat.org. Retrieved 2021-09-21.
  4. ^ "Bixbite (Red Beryl)". National Gem Lab. 2017-03-04. Retrieved 2021-09-21.