Usually very light in color--white, pink, grayish or blue--chalcedony is a translucent or transparent crypto crystalline variety of quartz almost always used in cabochon form of gems. It is most commonly found in the deep recesses of volcanic rocks. In antiquity, the most prized variety came from Chalcedon in Bythinia in Asia Minor. The Egyptians, Romans and peoples of the Holy Land frequently carved intaglios into it, preferring the milky white variety above all others. Medicinally, chalcedony is said to have the power to drive away fevers, to cure or prevent diseases of the eye (especially cataracts) and to aid in the relief of gallstones. It was one of the amuletic stones used by the ancients to banish bad dreams. Its soft colors are generally of the soothing variety, and those who chose to wear the stone are blessed with a peaceful and equable disposition.