BERYL
Beryl is a beryllium aluminosilicate, Be3Al2(Si6O18).
It has a nonmetallic luster, forms sharp, hexagonal crystals, is very hard
(H=7.5 to 8), and can be any color. A frequently encountered color is
pale bluish-green. Beryl has a glassy luster and no obvious cleavage
Transparent beryls are gemstones. The gem name
depends on the color.
deep green = emerald
bluish = aquamarine
pink = morganite
rich yellow = golden beryl
red = bixbite
yellowish-green to pale greenish = heliodor
clear/colorless = goshenite
Beryl
- two broken crystals (lower sample is 5.6 cm across) from a pegmatite in the Sao
Francisco Craton's basement in southeastern Minas Gerais State, southeastern
Brazil.
Emerald
(chromiferous beryl) (green) + calcite (whitish) and pyrite (brassy gold) on
black carbonaceous shale (3.6 cm across). From the Muzo Hydrothermal
Emerald Deposit (lower Carbonaceous Shale Member, Paja Formation, Aptian Stage,
upper Lower Cretaceous) in the Muzo area, WSW of Chiquinquira, NNW of Bogotá,
western Boyaca Department, northwest-central Colombia.
Emerald
(chromiferous beryl) - large cluster from Russia (CM public display, Carnegie
Museum of Natural History, Pittsburgh, Pennsylvania, USA).
Emeralds
(green) in quartz matrix from Wenshan, China. Dwyer Mercer County
District Library collection, Celina, Ohio, USA.
Emerald
(green) in matrix from Coscuez, Colombia. Specimen owned by Stan &
Pris Woollams.
Emerald
from Brazil (public display, Field Museum of Natural History, Chicago,
Illinois, USA).
Aquamarine (upper crystal is 20 mm across) - they look clear, but the actual
specimens are blue - very, very, very pale blue. These come from a
Precambrian, gem-bearing pegmatitic granite in the Jos Plateau of central
Nigeria.
Aquamarine (public display, Cleveland Museum of Natural History, Cleveland, Ohio,
USA).
Aquamarine (Dwyer Mercer County District Library collection, Celina, Ohio, USA)
Aquamarine from Medina, Minas Gerais State, Brazil (Wayne State University
specimen, Detroit, Michigan, USA).
Aquamarine from Shigar Valley, Pakistan. (Wayne State University specimen,
Detroit, Michigan, USA)
Morganite (manganiferous beryl) from Minas Gerais State, Brazil. (Cranbrook
Institute of Science collection, Bloomfield Hills, Michigan, USA)
Morganite (manganiferous beryl) from California, USA (Field Museum of Natural
History, Chicago, Illinois, USA).
Heliodor
(beryl with uranium oxide as pigmentation agent).
Heliodor
from the Murzinska Mine, Murzinska Pegmatite District, Urals, Russia.
(Wayne State University specimen, Detroit, Michigan, USA)
Goshenite from Teofilo Otoni, Minas Gerais State, Brazil.
(Wayne State University collection, Detroit, Michigan,
USA)
Goshenite from Pakistan (public display, Field Museum of Natural History, Chicago,
Illinois, USA).