Amethyst of synthetic quartz is used. Treated amethyst is produced by gamma ray, X-ray or electron beam irradiation of clear quartz (rock crystal) which has been first doped with ferric impurities. On exposure to heat, the irradiation effects can be partially cancelled and amethyst generally becomes yellow or even green, and much of the citrine, cairngorm, or yellow quartz of jewelry is said to be merely "burnt amethyst". The Greek word "amethystos" may be translated as "not drunken", from Greek "a-", "not" + "methustos", "intoxicated". Amethyst was considered to be a strong antidote against drunkenness, which is why wine goblets were
Amethyst gasfield Amethyst gasfield Amethyst is a natural gas field in the Southern North Sea, about east of the Yorkshire coast. Gas lies in a Permian sandstone reservoir around below the seabed. The gasfield is operated by BP. The gasfield was discovered in 1972 and it was named after HMS "Amethyst". Between 1972 and 1985 a number of appraisal wells were drilled. The field development started in 1988 and the first gas was produced in 1991. Originally, the field was owned by BP, Enterprise Oil, British Gas, ARCO, Murphy Oil, Amerada Hess, and FINA. In 1997, BP acquired the interest of Enterprise