26 Nisan 2013 Cuma

New Hampshire State Mineral

New Hampshire State Mineral

Beryl

STATUS
Official
DESCRIPTION
Beryl is a beryllium aluminum silicate, sometimes with some sodium, lithium, and cesium also present. Pure beryl is colorless, but impurities cause the mineral to occur in a wide variety of colors, including bright to pale green, light to dark blue, blue-green, yellow, pink, purple, red, brown, white, and gray. This mineral is naturally transparent but may be opaque due to inclusions. Certain specimens display asterism, or a star effect.
The many varieties of beryl are classified by their color, which comes from the additional minerals present during formation. Some of the more well-known beryls include emerald, the medium- to dark-green variety due to chrome and/or vanadium impurities; aquamarine, the light blue to blue-green variety due to iron impurities; morganite, the pink to light purple variety due to manganese impurities; and heliodor, the yellow, yellow-green, or brown variety due to iron and uranium impurities. There are a number of lesser-known varieties of beryl, all called precious beryl, and many simply named according to their color, such as red beryl and golden beryl. The rare colorless beryl is called goshenite after the location where it was first described, Goshen, Massachusetts.
It should be noted that despite its name, the gemstone chrysoberyl is not a form of beryl. It has a different chemical structure.
STATE SYMBOL
Beryl is commonly found in the abundant granite of New England. Beryl was designated the official state mineral of New Hampshire in 1985.
NAME ORIGIN
The word "beryl" is possibly from the Greek beryllos, which once referred to a number of blue-green stones.
FORMATION AND OCCURRENCE
Beryl is commonly found in course-grained granites and igneous rocks derived from granite, known as pegmatites. Red beryl is found in fine-grained, extrusive topaz. Beryl is famous for its perfect hexagonal crystals. Some enormous, well-formed crystals of up to 30 feet (8 m) in length exist. This mineral also occurs as short, stubby crystals in masses and as columnar aggregate.
Deposits in the Wah Wah Mountains and the Thomas Range Mountains in Utah are the only known deposits in the world to produce fine-quality red beryl suitable for faceting. New England has produced some of the largest beryl specimens in the world. One crystal from the Bumpus Quarry in Albany, Maine, is 18 feet by 4 feet (5.5 m by 1.2 m).
GEOGRAPHIC DISTRIBUTION
The following is a list of localities with high-quality specimens of beryl.
  • Russia: Mursinka-Alabashka area, near Yekaterinburg (Sverdlovsk), Ural Mountains, and Nerchinsk south to Borzya, Adun-Chilon Mountains, Siberia
  • Ukraine: Volhynia
  • Mozambique: Muiâne pegmatite, Alto Ligonha district
  • Madagascar: Mt. Bity, south of Antsirabe; and the Malakialina district
  • Nigeria: Rafin-Gabas Hills, near Jos
  • Zimbabwe: Sandawana-Belingwe area, Mweza Range
  • Colombia: Muzo and Chivor districts, Boyacá Province
  • Brazil: Minas Gerais, Teófilo Otoni, Governador Valadares, Conselheiro Pena, and Itabira
  • Pakistan: Mingora, Swat district; Dassu and the Skardu district; Kunar and Nagar, near Karimabad, Hunza district
  • Afghanistan: Khenj, Panjshir Valley
  • United States: Pala and Rincon districts, San Diego County, California; Hiddenite, Alexander County, North Carolina; Wah Wah Mountains, Beaver County, Utah; Mt. Antero, Chaffee County, Colorado; and Sawtooth Mountains area, Idaho
USES
Historical Uses
Many varieties of beryl have been used as gemstones since prehistoric times. It is one of the most important gem minerals. This gem is usually faceted, and is most suited to square and rectangular cuts to bring out its true beauty. The rarest and most expensive variety is red beryl, found only in Utah. The most common gem-quality beryl is golden beryl. Due to its transparency, colorless goshenite was previously used to manufacture lenses and eyeglasses. Although rare, goshenite is not very valuable.
Modern Uses
The mineral beryl is a source of the element beryllium, which is used mainly to strengthen metal alloys because of its low weight, strength, and high melting point. For these same reasons, beryllium is also important in aerospace and defense applications. Springs, gears, and gasoline pumps may also be made of beryllium.
Legend
Beryl is believed to drive evil spirits away and to protect travelers from danger. Some believe it has the power to treat disorders of the heart and spine. Pliny reportedly used beryl in powdered form to cure eye injuries. Other legends about beryl indicate it was used to promote cheerfulness and marital love, to discourage laziness, and to maintain youthfulness.
BIRTHSTONE
Beryl is the zodiac birthstone for Scorpio and the talismanic stone for Sagittarius.
State Mineral
Beryl Specimen
State Mineral
Isolated Clear Beryl Sample
State Mineral
Beryl Occurs in a Range of Colors
State Mineral
Pink Beryl
BERYL FACTS
Group: Silicate 
Chemical Formula: Be3Al2(SiO3)6
Crystal Structure: Hexagonal (6/m 2/m 2/m) Space group: P 6/mсc
Hardness (Mohs): 7.5-8
Color: Green, blue, yellow, colorless, pink & others.
Transparency: Transparent to opaque
Luster: Vitreous
Density: Average 2.76
Streak: White
Cleavage: Imperfect on the [0001]
Fracture: Conchoidal
Tenacity: Brittle
Some data courtesy of the Mineralogical Society of America
Author: World Trade Press

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