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Amethyst is a violet variety of quartz. The name comes from the Koine Greek αμέθυστος amethystos from α - a- , "not" and μεθύσκω ( Ancient Greek ) methysko / μεθώ metho ( Modern Greek ), "intoxicate", a reference to the belief that the stone protected its owner from drunkenness . [ 1 ]
Not every yellow quartz is considered citrine, and there is disagreement as to when the name "citrine" is appropriately used. However, quartz stained by iron inclusions or coatings is generally not considered citrine. Natural citrine is rare; most commercially available citrine is produced by heating amethyst or smoky quartz. Natural citrine ...
Prasiolite (also known as green quartz, green amethyst or vermarine) is a green variety of quartz. Since 1950, almost all natural prasiolite has come from a small Brazilian mine, [citation needed] but it has also been mined in the Lower Silesia region of Poland. Naturally occurring prasiolite has also been found in the Thunder Bay area of ...
Leaders of states in the U.S. which have significant mineral deposits often create a state mineral, rock, stone or gemstone to promote interest in their natural resources, history, tourism, etc. Not every state has an official state mineral, rock, stone and/or gemstone, however.
Quartz is, therefore, classified structurally as a framework silicate mineral and compositionally as an oxide mineral. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. [9] Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation ...
The five cardinal gems. Clockwise from top: sapphire, ruby, emerald, amethyst, diamond. Cardinal gems are gemstones which have traditionally been considered precious above all others. The classification of the cardinal gems dates back to antiquity, and was largely determined by ceremonial or religious use as well as rarity. [1]
Heat can either improve or spoil gemstone color or clarity. The heating process has been well known to gem miners and cutters for centuries, and in many stone types heating is a common practice. Most citrine is made by heating amethyst, and partial heating with a strong gradient results in "ametrine" – a stone partly amethyst and partly citrine.
The Greek name amethystos alludes to the popular belief that amethyst prevented intoxication; as such, drinking vessels were made of amethyst for festivities, and carousers wore amulets made of it to counteract the action of wine. [6] The amethyst is a brilliant transparent stone of a purple color and varies in shade from violet purple to rose.