Red Beryl occurs as hexagonal crystals which is typical of beryl. The refractive index is 1.564-1.574 and the specific gravity is 2.66-2.70. It's primary chemical composition is Be3Al2SiO3, but there are traces of many other elements. A more detailed examination including geological, chemical, physical and gemological information can be found in the magazine Gems and Gemology, Volume XX, Winter 1984.
Red Beryl is thought to have formed along fractures, in cavities or within the host rhyolite from a high-temperature gas or vapor phase released during the latter stages of cooling and crystallization of the rhyolite magma. Rhyolites ordinarily lack gem minerals and beryls of any sort is extremely uncommon, therefore the presence of Red Beryl suggests some unusual conditions for gemstone formation.
Red Beryl crystals range in color from orange-red to purplish-red with medium tones. The largest crystal yet recovered was 14mm x 34mm and weighed approximately 54 carats. The average faceted gemstone is .15 carats and the largest faceted gemstone to date weighed 8.0 carats.
Red Beryl description and images provided by Tim Schmanski.