Agate

Published: June 20, 2007

Types: Agate is a variety of chalcedony quartz that forms in curved or concentric bands. It is an alternative birthstone for May. Blue lace agate is characterized by light-blue bands. Botswana agate contains shades of tan, pink, and white. Other varieties of agate include banded agate, moss agate, tree agate, and fossil agate.

History: In ancient times, agates were used as talismans and amulets.

Origins: Major sources of agate are Brazil, India, Mexico, Russia, and the United States.

Treatments: Some agates - particularly black, blue, and green agates - may undergo dyeing. These treatments are relatively stable and require no special care. Blue lace, Botswana, and moss agates are rarely treated.

Availability and cost: Agates are readily available and reasonably priced. A 16-in. (41cm) strand costs $3-$23 depending on the type and size.

Care: Agates are very durable. They are usually safe in ultrasonic and steam cleaners, but warm, soapy water is best.

Related Issues

May 2006