Birthstone for: December

The alternate birthstone for December is the zircon. Its name is probably derived from the Arabic words "zar" and "gun", meaning "gold" and "color". The gemstone is found in a wide range of colors, and possess great brilliance, fire and clarity. Zircon, in its unchanged natural form appears colorless to pale yellow, or green. These colors are caused by minute quantities of thorium and uranium that replaces zircon in the crystal structure. But over the vast spans of geologic time, other forces work within the zirconium silicate crystals. The uranium and thorium inclusions emit radiation that alters the original crystal structure. A glass-like material is formed, with colors of red to brown, orange and yellow.