Listing description
Aquamarine (from Lat. aqua marina,
"water of the sea") is a blue or turquoise variety of beryl. It occurs at most
localities which yield ordinary beryl, some of the finest coming from Russia
Detailed descrption
Aquamarine
(from Lat. aqua marina, "water of the sea") is a blue or turquoise variety of beryl. It occurs at
most localities which yield ordinary beryl, some of the finest coming from Russia.
The gem-gravel placer deposits of Sri
Lanka contain aquamarine. Clear yellow beryl, such as occurs in Brazil,
is sometimes called aquamarine chrysolite. When corundum
presents the bluish tint of typical aquamarine, it is often termed Oriental
aquamarine. The deep blue version of aquamarine is called maxixe. Its
color fades to white when exposed to sunlight or is subjected to heat
treatment, though the color returns with irradiation.The pale blue color of aquamarine is attributed to Fe2+. The 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 Fe3+ and Fe2+.[6][7][8][9] Dark-blue maxixe color can be produced in green, pink or yellow beryl by irradiating it with high-energy particles (gamma rays, neutrons or even X-rays).[10]
In the United States, aquamarines can be found at the summit of Mt. Antero in the Sawatch Range in central Colorado. In Wyoming, aquamarine has been discovered in the Big Horn Mountains, near Powder River Pass. 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, Zambia, Madagascar, Malawi, Tanzania and Kenya also produce aquamarine.
The biggest aquamarine ever mined was found at the city of Marambaia, Minas Gerais, Brazil, in 1910. It weighed over 110 kg, and its dimensions were 48.5 cm (19 in) long and 42 cm (17 in) in diameter.
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Aquamarine
is the blue, or perhaps more correctly, blue-green or aqua variety of the
mineral beryl. Other gemstone color
varieties that are also the mineral beryl include emerald, morganite, and heliodor. Other colors of beryl
are simply referred to by their color, such as red beryl. Aquamarine is colored
by trace amounts of iron. Most gem aquamarines have been heat treated to
produce the popular blue-green colors from less desirable yellow or pale
stones. The leading producer of aquamarines is the country of Brazil, which
has many mines. Pakistan, as well as many U.S. localities, produce wonderful
specimens as well. Recently, a new mine in China has produced large numbers
of excellent flat (stubby) hexagonal crystals, for a fraction of the price of
those beautiful Pakistan specimens.
Aquamarine is sometimes found in huge crystals (unlike
emerald). It is also known in a glassy form, often without showing
crystal form, and sometimes with many holes or other odd shapes. Other
times a large cluster of prismatic crystals can be seen to all have the same
alignment - a sign that it is really a single crystal with many faces.
Aquamarine often forms perfect, flawless crystals - also unlike
Emerald for which flawless natural crystals are extremely rare.
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Deposits
Beryl
of various colors is found most commonly in granitic pegmatites,
but also occurs in mica schists in the Ural Mountains, and limestone
in Colombia.
Beryl is often associated with tin and tungsten ore bodies. Beryl is found in Europe
in Norway,
Austria,
Germany,
Sweden
(especially morganite), and Ireland, as well as Brazil, Colombia, Madagascar, Mozambique,
Russia,
South
Africa, the United States, and Zambia.
U.S. beryl locations are in California,
Colorado,
Connecticut,
Idaho,
Maine,
New Hampshire, North
Carolina, South Dakota and Utah.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 5.5 m by 1.2 m (18 ft by 4 ft) with a mass of around 18 metric tons; it is New Hampshire's state mineral. As of 1999, the largest known crystal of any mineral in the world is a crystal of beryl from Madagascar, 18 meters long and 3.5 meters in diameter.[5]
Varieties
Emerald
Emerald
refers to green beryl, colored by trace amounts of chromium
and sometimes vanadium.[6][11]
The word "emerald" comes (via Middle
English: Emeraude, imported from Old
French: Ésmeraude and Medieval
Latin: Esmaraldus) from Latin smaragdus
from Greek smaragdos - σμάραγδος ("green gem"), its
original source being a Semitic word izmargad (אזמרגד)
or the Sanskrit
word, marakata (मरकन),
meaning "green".[12]
Most emeralds are highly included, so their brittleness (resistance to breakage) is classified as
generally poor.Emeralds in antiquity were mined by the Egyptians and in Austria, as well as Swat in northern Pakistan.[13] 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 most rare emeralds come from three main emerald mining areas in Colombia: Muzo, Coscuez, and Chivor. 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 the Yukon.
Emerald is a rare and valuable gemstone and, as such, it has provided the incentive for developing synthetic emeralds. Both hydrothermal[14] 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 1 mm per month, a typical seven-month growth run producing emerald crystals of 7 mm of thickness.[15] The green color of emeralds is attributed to presence of Fe3+ and Fe2+ ions.[7][8][9]
Golden beryl and heliodor
Golden beryl can range in colors from pale
yellow to a brilliant gold. Unlike emerald,
golden beryl has very few flaws. The term "golden beryl" is sometimes
synonymous with heliodor (from Greek hēlios - ἥλιος
"sun" + dōron - δῶρον "gift") but golden beryl
refers to pure yellow or golden yellow shades, while heliodor refers to the
greenish-yellow shades. The golden yellow color is attributed to Fe3+
ions.[6][7]
Both golden beryl and heliodor are used as gems. Probably the largest cut
golden beryl is the flawless 2054 carat
stone on display in the Hall of Gems,
Washington, D.C.[16]
Goshenite
Colorless
beryl is called goshenite. The name originates from Goshen, Massachusetts where it was originally
described. Since all these color varieties are caused by impurities and pure
beryl is colorless, it might be tempting to assume that goshenite is the purest
variety of beryl. However, there are several elements that can act as inhibitors
to color in beryl and so this assumption may not always be true. The name
goshenite has been said to be on its way to extinction and yet it is still
commonly used in the gemstone markets. Goshenite is found to some extent in
almost all beryl localities. In the past, goshenite was used for manufacturing
eyeglasses and lenses owing to its transparency. Nowadays, it is most commonly
used for gemstone purposes and also considered as a source of beryllium.[17][18]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.[7]
Morganite
Morganite,
also known as "pink beryl", "rose beryl", "pink
emerald", and "cesian beryl", is a rare light pink to
rose-colored gem-quality variety of beryl. Orange/yellow varieties of morganite
can also be found, and color banding is common. It can be routinely heat
treated to remove patches of yellow and is occasionally treated by irradiation
to improve its color. The pink color of morganite is attributed to Mn2+
ions.[6]Pink beryl of fine color and good sizes was first discovered on an island on the coast of Madagascar in 1910.[19] It was also known, with other gemstone minerals, such as tourmaline and kunzite, at Pala, California. In December 1910,the New York Academy of Sciences named the pink variety of beryl "morganite" after financier J. P. Morgan.[19]
On October 7, 1989, one of the largest gem morganite specimens ever uncovered, eventually called "The Rose of Maine," was found at the Bennett Quarry in Buckfield, Maine, USA.[20] The crystal, originally somewhat orange in hue, was 23 cm (9 in) long and about 30 cm (12 in) across, and weighed (along with its matrix) just over 50 lbs (23 kg).[21]
Red beryl
Red
beryl (also known as "red emerald" or "scarlet emerald") is
a red variety of beryl. It was first described in 1904 for an occurrence, its type locality, at Maynard's Claim (Pismire
Knolls), Thomas Range, Juab
County, Utah, USA.[22][23]
The old synonym bixbite is deprecated from the CIBJO,
because of the risk of confusion with the mineral bixbyite
(also named after the mineralogist Maynard
Bixby). The dark red color of bixbite is attributed to Mn3+
ions.[6]Red beryl is very rare and has only been reported from a handful of locations including: Wah Wah Mountains, Beaver County, Utah; Paramount Canyon, Sierra County, New Mexico; Round Mountain, Sierra County, New Mexico;[1] and Juab County, Utah. The greatest concentration of gem-grade red beryl comes from the Violet Claim in the Wah Wah Mountains of mid-western Utah, discovered in 1958 by Lamar Hodges, of Fillmore, Utah, while he was prospecting for uranium.[24] Prices for top quality natural red beryl can be as high as $10,000 per carat for faceted stones. Red beryl has been known to be confused with pezzottaite, also known as raspberry beryl or "raspberyl", a gemstone that has been found in Madagascar and now Afghanistan - although cut gems of the two varieties can be distinguished from their difference in refractive index.
PRICE
$24.6/KG OR $12/IB
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