28 Nisan 2013 Pazar

Maine State Gemstone

Maine State Gemstone


Amethyst is the most precious variety of quartz. Composed of silicon dioxide, amethyst is colored light pinkish violet to deep purple by iron and aluminum impurities.
Although Maine does not have an official gemstone, amethyst represents the state well because a large number of amethyst crystals have come from western Maine in recent years. A three-foot specimen mined in Sweden, Maine, in 1989 is now on display at the National Museum of Natural History in Washington, DC.
South Carolina designated amethyst its official gemstone in 1969.Amethyst is also one of two forms of quartz designated as the state gems of Georgia in 1976. 
The name for this stone comes from the Greek from Greek a- (not) + methustos (intoxicated), a reference to the belief that the stone protected its owner from drunkenness.
Amethyst occurs in crystalline or massive forms. This stone can occur as six-sided crystals or as drusy, which are crystalline crusts covering the host rock. It is found in alluvial deposits and inside geodes all over the world.
Historical Uses
A favorite of Egyptian and British royalty, amethysts are featured in the British Crown Jewels. The gem was also called "the stone of bishops," as it was prized in the high ranks of the Catholic Church. Since ancient Greeks and Romans believed amethyst would prevent intoxication, they wore amethyst and made wine goblets from the stone. Ancient Egyptians used amethyst in engraved intaglios.
Modern Uses
Formerly considered a precious gem, amethyst lost much of its status and value once large deposits were discovered. However, it remains prized for its beautiful color. Because amethyst is very common, it is an inexpensive and widely used stone. Most amethyst is faceted into gemstones, and is sometimes cut into cabochons. The best gems are transparent and free of visible inclusions. Large, massive chunks of amethyst banded with quartz are sometimes carved into ornaments. Collectors look for geodes, tumbled stones, and rare prismatic crystals. The rarest stones, called Deep Russian, are very valuable.
Heating can enhance amethyst’s purple color or turn it yellow-brown to dark brownish. Much of the citrine, a yellow to brown variety of quartz, and smoky quartz sold in jewelry today are artificially formed by heat-treating amethyst.
In Greek mythology, Dionysus, the god of wine, ritual madness, and ecstasy, was pursuing a maiden named Amethystos. She refused his advances and prayed to the god Artemis to keep her chaste. Artemis answered her by turning her into a white stone. Dionysus then poured wine over Amethystos, turning the crystals purple. Another variation says that the goddess Rhea, "the mother of gods," gave Dionysus the amethyst stone to preserve the wine-drinker’s sanity.
Amethyst is said to be of help for headaches, the pancreas, hearing disorders, insomnia, and backache. Because of its connection to wine and sobriety, it is said to be helpful in overcoming addiction.
Amethyst is the traditional birthstone for February and the stone for the zodiac sign of Pisces. This gem is the planetary stone of Neptune. Amethyst is suggested as a gem to give on the fourth, sixth, and 17th wedding anniversaries.
Synthetic amethyst has chemical and physical properties so similar to genuine amethyst that without expensive gemological testing, they cannot be differentiated.
State Gemstone
Amethyst Crystals
State Gemstone
Collection of Amethyst Stones
State Gemstone
Perfect Amethyst Gem
Group: Quartz
Chemical Formula: SiO2
Crystal Structure: Trigonal
Hardness (Mohs): 7; lower in impure varieties
Color: Violet to deep purple
Transparency: Transparent
Luster: Vitreous
Birefringence: +0.009 (B-G interval)
Pleochroism: None
Refractive Index: 1.544-1.553 - Dr +0.009 (B-G interval)
Density: 2.65 constant; variable in impure varieties
Streak: White
Cleavage: None
Fracture: Conchoidal

Some data courtesy of the Mineralogical Society of America
Author: World Trade Press

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