Description
Amethyst is a violet variety of the mineral quartz (SiO2) and is the most sought-after stone of the quartz group. Etymology: The name comes from the Greek αμεθυστoς (amethystos). Amethyst was already known to the Egyptians, Etruscans, and Romans, and was described by Pliny the Elder. In ancient China, small gems were cut from amethyst. In the Middle Ages, amethyst was also highly prized in Europe. It was called the bishop's stone because it was once a favored gemstone for ecclesiastical dignitaries and was said to possess magical powers. It was the symbol of lovers, the stone of temperance, and a protector against sorcery and witchcraft. Jacob van Maerlant explains that the stone dispels drunkenness. It has been assumed that the Greek name means "against intoxication": one would not get drunk from wine drunk from an amethyst cup. The stone's origins include metamorphic, hydrothermal, and alluvial deposits. The crystals always grow on a substrate; the prisms are often weakly developed, and therefore the crystal points of amethyst predominate; here, the color is also most intense. These parts are knocked off, that is, broken off for further use. Firing at temperatures between 470 and 750 degrees Celsius produces light yellow, reddish-brown, green, or colorless varieties. Some amethysts gradually fade in daylight. Radium irradiation can restore the original color. The color is caused by iron in combination with ionizing radiation. Amethyst is less attractive in artificial light. Occurrence: Brazil boasted its amethyst deposits as far back as the Middle Ages. They are mined in Bahia, Minas Gerais, and Mato Grosso, among other places. Recently, amethyst, an amethyst-citrine, has been mined in Bolivia, where the violet and yellow colors alternate, but the transition between the colors is sharply defined. Amethysts are also known in the United States, namely in Montana, Maine, Georgia, and Arizona. Canada, Mexico, Bolivia, India, Myanmar, Japan, China, and Korea, as well as Sri Lanka, Zimbabwe, Congo, and Australia, are also important producers. In Russia, amethyst is found in the Urals, Yakutsk, and on the Kola Peninsula, among other places. Amethysts are also found in Armenia, Germany, the Czech Republic, Slovakia, Bulgaria, Switzerland, and Ireland. Amethyst rarely forms larger, pure crystals. The British Museum houses a unique cut stone weighing 343 carats. Other, smaller stones weigh less; they usually come from Brazil. The Smithsonian Institution in Washington, D.C., even owns a 1,362-carat cut amethyst from Brazil and one from North Carolina weighing 202.5 carats. Amethysts were often used in state jewels, such as Catherine the Great's scepter and the British Crown Scepter.
