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Beryl Family:
Cyclosilicates (Beryllium aluminum silicate, frequently with some sodium, lithium and cesium) Be3Al2Si6O18 AKA: Aquamarine, Emerald, Golden beryl, Heliodor, Goshenite, Morganite |
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System: Hexagonal; crystals common, usually six-sided prisms that are striated lengthwise. Appearance: Color varies. Usually grayish-white, yellowish-white or pale blue-green, but some varieties are transparent: golden beryl, golden yellow; aquamarine, greenish blue; morganite, red, pink; heliodor, yellow and brown; goshenite, colorless. The prism faces are often finely striated. Vitreous luster. Often contains a great many inclusions, making it opaque. White streak. Physical Properties: Hardness: (7.5 - 8.0); Specific gravity: (2.66 - 2.92); Cleavage: Indistinct, one direction; fracture, uneven to conchoidal; transparent to translucent. Similar species: Beryl is harder than apatite, quartz and the feldspars; does not have the cleavage of feldspars; and it is striated the length of the crystal, whereas quartz is striated crosswise. Occurrence: Beryl develops in pegmatites and certain metamorphic rocks. Opaque beryl is common in several places in Brazil, Malagasy Republic, the USA, Czechoslovakia, India and the former USSR. Emerald comes mainly from the mines at Muzo, Chivor and Somondoco (Colombia). The best aquamarine for cut stones comes from Brazil, the Urals, India, Namibia and Ireland. Morganite, the only beryl variety found in stubby or tabular prisms, comes from Pala and Ramona, California (USA), from Brazil and Malagasy Republic. Heliodor is found in Siberia, Namibia, Malagasy Republic and Brazil. Miscellaneous: Beryl as a gemstone refers to all varieties of the beryl group which are not emerald-green or aquamarine blue. Emerald is one of the most highly prized gemstones, and is one of the darkest of the beryl family. All the other gemstones are light in color. All gemstones made of beryl are faceted. Individual crystals are sometimes enormous, up to 9m (30 ft) long and weighing 25 tons. Emerald is the birthstone for May; aquamarine, for October. The name is from the Greek beryllos, indicating any green gemstone. Beryl is also valuable industrially as a source of beryllium for use in the manufacture of alloys. Conventional Wisdom: Beryl was widely known in antiquity, when it was a favorite healing and divination stone thought to empower incantations. Greek physicians dosed patients with water into which beryl had been dipped as a cure for bladder and kidney stones. Medieval doctors claimed that beryl could cure jaundice and liver disease, as well as laziness. It could also reconcile married couples, revive fading love, and bring victory in battle or litigation. It used to be thought that the most suitable stone for crystal gazing was not quartz but beryl, especially during the waxing moon, when the stone was said to accumulate "lunar magnetism". Helps heart problems, liver trouble, mouth, stomach and throat infections. Improves intellect,strengthens will-power, guards against stupidity and mental disorders. Belongs to the Astrological Signs of Gemini, Pisces and Aries (Aquamarine); Taurus, Gemini and Aries (Emerald); Leo (Golden beryl); Leo (Helidor); Libra (Morganite) |