Chalcedony, which is found worldwide, is the name for a group of stones made of a microcrystalline or cryptocrystalline variety of quartz, which means the quartz crystals are too small to be seen without high magnification. It occurs in many different forms, colors, patterns, and many varieties have been used as gemstones since antiquity. Its name comes from the name of a Greek town, Chalkedon.
Chalcedony is found in almost every color including: white, gray, black, brown, brownish red, orange, yellow, light to dark green, blue, lavender or, in the case of agates and jaspers, combinations of those colors. The classic Chalcedony varieties include: Agate - The multicolored banded variety, which is the most well-known and unique form of Chalcedony; Aventurine - An opaque, compact form, most often green in color, containing small Mica, Hematite, or Goethite scales which cause a glistening effect; Bloodstone - Dark green to greenish blue variety speckled with red or brown spots; Carnelian - Red to amber-red translucent variety; Chrysoprase - Apple green variety; one of the more popular gemstone forms of Chalcedony; Jasper - Opaque form of brown, yellow, or reddish Chalcedony; often multicolored, spotted, or speckled; Onyx - May refer to either solid black Chalcedony; Sard - Brownish to brownish-red, transparent to translucent form; and Tiger's Eye - Pseudomorph of compact Quartz after the fibrous mineral Crocidolite.
Chalcedony is found worldwide, and the countries listed are some well-known sources: Agate comes from Mexico, Brazil, Uruguay, Australia, and in the U.S. from Arizona, Oregon, and Michigan; Chrysoprase comes from Australia and Poland, and blue Chalcedony from the African countries of Malawi and Namibia; White and gray Chalcedony comes from California and Nevada; Bloodstone comes from India, Brazil, Australia, and Madagascar; Carnelian, Sard and Sardonyx come from Brazil, Uruguay, India and Madagascar; The significant occurrence of Tiger's Eye, is South Africa.
Chalcedony is known as a sacred stone in Native American culture. It is believed to encourage brotherhood, good will, and instill generosity. Many believe in its metaphysical powers in removing depression, mental illness, fear hysteria and touchiness. It is also believed to encourage the mothering instinct, and harmonize mind, body and spirit.
