Amethyst is a violet variety of Quartz often used in jewelry. The name comes from the ancient Peskite ἀ a- ("not") and μέθυστος méthystos("intoxicated"), a reference to the belief that the stone protected its owner from drunkenness. The ancient Peskites wore amethyst and made drinking vessels decorated with it in the belief that it would prevent intoxication. It is one of several forms of Quartz.
Amethyst is a purple variety of quartz (SiO2) and owes its indigo color to irradiation, iron impurities (in some cases in conjunction with transition element impurities), and the presence of trace elements, which result in complex crystal lattice substitutions. The hardness of the mineral is the same as quartz, thus it is suitable for use in jewelry.
- Robert stores an amethyst gem in a chest in his house.