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Beryl ( ) is a mineral composed of beryllium aluminium silicate with the chemical formula Be3Al2(SiO3)6. Well-known varieties of beryl include emerald and aquamarine. Naturally occurring hexagonal of beryl can be up to several meters in size, but terminated crystals are relatively rare. Pure beryl is colorless, but it is frequently tinted by impurities; possible colors are green, blue, yellow, pink, and red (the rarest). It is an ore source of beryllium. (2025). 9780471721574, J. Wiley. ISBN 9780471721574
When the first Glasses were constructed in 13th-century Italy, the lenses were made of beryl (or of Quartz) as glass could not be made clear enough. Consequently, glasses were named Brille in German"Brille"
retrieved 9 August 2024. ( bril in Dutch and briller in Danish).
New England's pegmatites have produced some of the largest beryls found, including one massive crystal from the Bumpus Quarry in Albany, Maine with dimensions with a mass of around ; it is New Hampshire's state mineral. , the world's largest known naturally occurring crystal of any mineral is a crystal of beryl from Malakialina, Madagascar, long and in diameter, and weighing .G. Cressey and I. F. Mercer, (1999) Crystals, London, Natural History Museum, page 58
The pale blue color of aquamarine is attributed to Fe2+. Fe3+ ions produce golden-yellow color, and when both Fe2+ and Fe3+ are present, the color is a darker blue as in maxixe. Decoloration of maxixe by light or heat thus may be due to the charge transfer between Fe3+ and Fe2+.
In the United States, aquamarines can be found at the summit of Mount Antero in the Sawatch Range in central Colorado, and in the New England and North Carolina pegmatites. (1964). 9780442276249, Van Nostrand. ISBN 9780442276249 Aquamarines are also present in the state of Wyoming, aquamarine has been discovered in the Big Horn Mountains, near Powder River Pass. Another location within the United States is the Sawtooth Range near Stanley, Idaho, although the minerals are within a wilderness area which prevents collecting. In Brazil, there are mines in the states of Minas Gerais, Espírito Santo, and Bahia, and minorly in Rio Grande do Norte. The mines of Colombia, Skardu Pakistan, Madagascar, Russia, Namibia, Zambia, Malawi, Tanzania, and Kenya also produce aquamarine.
The modern English word "emerald" comes via Middle English emeraude, imported from modern French via Old French ésmeraude and Medieval Latin esmaraldus, from Latin smaragdus, from Ancient Greek smaragdos meaning 'green gem'.
Emeralds in antiquity were mined by the Ancient Egypt and in what is now Austria, as well as Swat in contemporary Pakistan. A rare type of emerald known as a trapiche emerald is occasionally found in the mines of Colombia. A trapiche emerald exhibits a "star" pattern; it has raylike spokes of dark carbon impurities that give the emerald a six-pointed radial pattern. It is named for the trapiche, a grinding wheel used to process sugarcane in the region. Colombian emeralds are generally the most prized due to their transparency and fire. Some of the rarest emeralds come from the two main emerald belts in the Eastern Ranges of the Colombian Andes: Muzo and Coscuez west of the Altiplano Cundiboyacense, and Chivor and Somondoco to the east. Fine emeralds are also found in other countries, such as Zambia, Brazil, Zimbabwe, Madagascar, Pakistan, India, Afghanistan and Russia. In the US, emeralds can be found in Hiddenite, North Carolina. In 1998, emeralds were discovered in Yukon.
Emerald is a rare and valuable gemstone and, as such, it has provided the incentive for developing synthetic emeralds. Both hydrothermal and flux-growth synthetics have been produced. The first commercially successful emerald synthesis process was that of Carroll Chatham. The other large producer of flux emeralds was Pierre Gilson Sr., which has been on the market since 1964. Gilson's emeralds are usually grown on natural colorless beryl seeds which become coated on both sides. Growth occurs at the rate of per month, a typical seven-month growth run producing emerald crystals of 7 mm of thickness. The green color of emeralds is widely attributed to presence of Cr3+ ions. Intensely green beryls from Brazil, Zimbabwe and elsewhere in which the color is attributed to vanadium have also been sold and certified as emeralds. (2002). 9780971537118, Lapis International. ISBN 9780971537118 (1997). 9781897799895, Geological Society of London. ISBN 9781897799895
The gem value of goshenite is relatively low. However, goshenite can be colored yellow, green, pink, blue and in intermediate colors by irradiating it with high-energy particles. The resulting color depends on the content of Ca, Sc, Ti, V, Fe, and Co impurities.
Red beryl is very rare and has only been reported from a handful of North American locations: Wah Wah Mountains, Beaver County, Utah; Black Range, Black Range, Juab County, Utah; and Sierra County, New Mexico, although this locality does not often produce gem-grade stones. The bulk of gem-grade red beryl comes from the Ruby-Violet Claim in the Wah Wah Mts. of midwestern Utah, discovered in 1958 by Lamar Hodges, of Fillmore, Utah, while he was prospecting for uranium. Red beryl has been known to be confused with pezzottaite, a caesium analog of beryl, found in Madagascar and, more recently, Afghanistan; cut gems of the two varieties can be distinguished by their difference in refractive index, and the rough crystals easily by their differing crystal systems (pezzottaite trigonal, red beryl hexagonal). Synthetic red beryl is also produced. Like emerald and unlike most other varieties of beryl, the red ones are usually highly included.
While gem beryls are ordinarily found in pegmatites and certain metamorphic stones, red beryl occurs in topaz-bearing . It is formed by crystallizing under low pressure and high temperature from a pneumatolytic phase along fractures or within near-surface miarolitic cavities of the rhyolite. Associated minerals include bixbyite, quartz, orthoclase, topaz, spessartine, pseudobrookite and hematite.
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