Due to its popularity as a gemstone, several descriptive terms have been coined in the gem trade to describe the varying colors of amethyst. "Rose de France" is usually a pale pinkish lavender or lilac shade (usually the least sought color). The most prized color is an intense violet with red flashes and is called "Siberian", although gems of this color may occur from several locations other than Siberia, notably Uruguay and Zambia. In more recent times, certain gems (usually of Bolivian origin) that have shown alternate bands of amethyst purple with citrine orange have been given the name ametrine
Purple corundum, or sapphire of amethystine tint, is called Oriental amethyst, but this expression is often applied by jewellers to fine examples of the ordinary amethystine quartz, even when not derived from eastern sources. Professional gemological associations, such as the Gemological Institute of America (GIA) or the American Gemological Society (AGS), discourage the use of the term "Oriental amethyst" to describe any gem, as it may be misleadin.
Geographic Distribution
Amethyst occurs at many localities in the United States, but these specimens are rarely fine enough for use in jewelry. Among these may be mentioned Amethyst Mountain, Texas; Yellowstone National Park; Delaware County, Pennsylvania; Haywood County, North Carolina; and Deer Hill, and Stow, Maine. It is found also in the Lake Superior district. Amethyst is relatively common in northwestern Ontario, but uncommon elsewhere in Canada; it was selected as the provincial mineral of Ontario in 1975.
Value
Traditionally included in the cardinal, or most valuable, gemstones (along with diamond, sapphire, ruby and emerald), amethyst has lost much of its value due to the discovery of extensive deposits in locations such as Brazil.
Purple corundum, or sapphire of amethystine tint, is called Oriental amethyst, but this expression is often applied by jewellers to fine examples of the ordinary amethystine quartz, even when not derived from eastern sources. Professional gemological associations, such as the Gemological Institute of America (GIA) or the American Gemological Society (AGS), discourage the use of the term "Oriental amethyst" to describe any gem, as it may be misleadin.
Geographic Distribution
Amethyst occurs at many localities in the United States, but these specimens are rarely fine enough for use in jewelry. Among these may be mentioned Amethyst Mountain, Texas; Yellowstone National Park; Delaware County, Pennsylvania; Haywood County, North Carolina; and Deer Hill, and Stow, Maine. It is found also in the Lake Superior district. Amethyst is relatively common in northwestern Ontario, but uncommon elsewhere in Canada; it was selected as the provincial mineral of Ontario in 1975.
Value
Traditionally included in the cardinal, or most valuable, gemstones (along with diamond, sapphire, ruby and emerald), amethyst has lost much of its value due to the discovery of extensive deposits in locations such as Brazil.
Source from Wikipedia
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