Amethyst belongs to the quartz family and is composed primarily of silica (SiO2). The violet color is caused by trace amounts of ferric iron. Amethyst crystals are found in vertical, hollow, gas tubes that formed in molten basalt. The gas tubes then became filled with silica-bearing solutions. This caused the amethyst to grow very slowly and line the inside walls of the gas tubes.
Amethyst is a very popular semi-precious stone and is used for faceting and jewelry making. The Greeks named the stone amethyst, meaning "without drunkenness". They used it constantly to protect themselves from overindulgences with food and drink.
Origine: South America.
Measure: 3" to 4".