Amethyst is an extremely sought-after gem which has been valued by many civilizations since antiquity. A variety of vitreous quartz, amethyst often forms dramatic prismatic crystals which are often formed into jewelry without being cut. Brazil and Uruguay are common sources of high quality amethyst. In the early Christian church, amethyst was believed to guard against intoxication, hence its derivation from the Greek "amethustos," meaning "not drunk."
Spring green peridot is the gem variety of ovaline, a silicate mineral thought to be common in the upper mantle of Earth's crust. Peridot-grade ovaline is most abundant in Pakistan and other dry areas. Used as early as 1580 BC in Egypt, peridot is held as a symbol of the Sun.