Amethyst essays

Amethyst essays The name for the mineral amethyst comes from the Greek word amethustos which means not drunken. In the first century a famous Greek god wrote that amethyst was named for its color being nearly the same as the color of wine. Early Greeks believed that drinking wine from an amethyst cup would prevent intoxication, or getting drunk. Amethyst is a purple gemstone. Iron and manganese compounds or impurities cause this purple coloration. The purple color of amethyst is due to small amounts (approximately 40 parts per million) of iron (Fe4+) impurities at certain areas in the crystal structure of quartz. The difference between amethyst and citrine is only the Oxidation State of the iron impurities in the quartz. When heated, the iron impurities are reduced and the amethyst's purple color fades and becomes yellow to reddish-orange (citrine), green, or colorless depending on the area and the original oxidation state of the iron impurities currently and the amount and time of the heating. The amethystine color usually can come back by irradiation, which re-oxidizes the iron impurities. The process can be done in a laboratory, but not often and when done is very difficult to tell that the mineral is synthetic. The color can also come back by a natural process of decomposing of a nearby radioactive mineral. This is mostly a reversible process, but constant heating can change the distribution of the iron impurities at different sites within the quartz making it impossible to convert it back to amethyst by post irradiation. The heating process can occur naturally or synthetically. Its known to be one of the most valuable quartz stones and its also known to be high in price. Amethyst is readily available in all sizes and shapes. Amethyst is made out of crystalline quartz. Crystalline quartz is a dichroic crystal and if the quartz is heated it will change the color of the mineral into yellow, creating another gemstone or mineral called c...