Any of several minerals and gemstones composed of beryllium aluminum silicate. The best known beryls are emerald (green) and aquamarine (blue); other types are heliodor (yellow) and morganite (pink). Beryl crystals occur in granites and pegmatites. Gem quality beryl crystals are found worldwide. They have been gathered or mined since 3000 BCE. High quality beryl gems are mined in Columbia, Brazil, Zimbabwe, South Africa, Namibia, and the U.S. (Califonia, Maine, Connecticut, South Dakota, and North Carolina). The largest recorded beryl crystal was found in Madagascar; it weighed 36 tons and measured 60 feet long.
Synonyms and Related Terms
emerald (bright green); aquamarine (blue); heliodor (yellow to brown); morganite (pink to purple); goshenite (colorless); Beryll (Deut.); béryl (Fr.); beril (Fr.); berilo (Esp., Port.); beryl (Ned.)
Hexagonal system with prismatic crystals usually striated lengthwise. Cleavage is poor in one direction. Weakly pleochroic.
Fracture = uneven to conchoidal. Luster = vitreous. Streak = colorless.
Fluorescence = none to weak. Synthetic stones may appear opaque and dull red under long UV light.
|Mohs Hardness||7.5 - 8.0|
|Refractive Index||1.57 - 1.60|
Hazards and Safety
Beryllium is a known carcinogen.
Mineralogy Database: Beryl
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