October Birhtstone

Opal is the modern October birthstone and the accepted gem for the 13th wedding anniversary. The name opal is derived from the Sanskrit word "upala," as well as the Latin "opalus," meaning "precious stone."

To ancient Romans, the opal was a symbol of love and hope. Orientals called it the "anchor of hope." Arabs say it fell from the heavens in flashes of lightning. It was believed to make its wearer invisible, hence the opal was the talisman of thieves and spies. The opal was supposed to maintain a strong heart, prevent fainting, protect against infection, and cleanse foul-smelling air. During the Medieval period, a change in color intensity of an opal was believed to indicated if its wearer was ill or in good health.

The opal is a fragile hydrated silica material, made of submicroscopic silica spheres held together by more silica and water. It is a soft stone, easily altered in appearance by changes in heat and pressure. This mineral contains varying amounts of water within it that determine the appearance of the gemstone. When water evaporates out of an opal, the stone appears slightly smaller and the stress of the evaporation creates cracks on it. Many stones flash the colors of the rainbow when moved, due to the interference of light on small cracks and other internal structural differences. Opals also have characteristic colors due to impurities within the stone.

Quality Opal is very expensive, made more so by the caution that must be exercised in cutting, polishing and setting it into Opal jewelry. The most valuable opal pattern is the "harlequin," large angular patches of red, yellow and green resembling the checks on a clown's costume.

October Birthstones
Color is noted next to birth stone name.
Modern Birthstone - Opal (White or Black), Tourmaline (Pink or Green)
Traditional Birthstone - Tourmaline (Pink or Green)
Mystical Birthstone - Jasper Brown or Red)
Ayurvedic Birthstone - Opal (White or Black)
Other Birthstone - Pink Tourmaline (Pink), Zircon (White, Clear), Aquamarine (Blue)

Opals are formed in near-surface volcanic rocks, within cavities and cracks. In sedimentary volcanic ash rock, percolating water in the ground dissolves silica that eventually precipitates to form the opal, sometimes becoming the replacement material for fossils -- shells, bones, wood -- whose original material had dissolved away.

Most of the world's Opal deposits are found in Southern Australia. Australia produces about 95% of the world's opal supply. Other sources of this gemstone are Brazil, Mexico, Czechoslovakia and Nevada.

Diamond and Gemstone Jewelry | Opal Jewelry

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