Chalcedony is Quartz with a transparent grayish or milky hue. It is made up of microscopic crystals which are arranged in bands like fibers. It forms rounded crusts or stalactites in volcanic and sedimentary rocks. Chalcedony gemstones occur in many different colors and shapes- agates, jaspers, onyx, chrysoprase, and bloodstone are all different varieties.

The most popular versions of chalcedony are bloodstone, carnelian, chrysoprase, sard, plasma, prase, onyx, agate, flint, thundereggs, jasper, and petrified wood and dinosaur bones.
The colors of Chalcedony can range from yellow to pale blue to brown or gray with a surface which resembles wax. It is often used in Florentine mosaics called “Comesso”, which creates pictures out of thin cut semiprecious stones.

Chalcedony is inexpensive and thus popular. It is also believed by some to heal depression, reduce fever, strengthen the eyes, and chase away fears. The most valuable chalcedony is from India, Madagascar, Burma, Brazil, Mexico & USA.