Scientific Name: mineraloid
Chemical Formula: SiO2·nH2O – hydrated silicon dioxide
The incandescent opal adds a unique depth of color to jewelry. The luminescent spectrum of colors the Opal boasts ranges from colorless to white, milky blue, gray, red, yellow, green, brown and black. Opal is the birthstone for the month of October.
The Opal has been called “a gemstone which combines the best possible characteristics of the most beautiful of gemstones: the fine sparkle of Almandine, the shining purple of Amethyst, the golden yellow of Topaz, and the deep blue of Sapphire, so that all colors shine and sparkle together in a beautiful combination. ”
Opals naturally contain small spheres of silica gel which causes the fantastic array of colors. The spheres catch light as it passes through the gemstone and refract it in all colors of the rainbow. The opal is always new, always different.
Black Opal displays the most brilliant spectrum of colors. The Australian boulder opal is found in Queensland’s iron boulders. The iron in this precious opal causes an unusually rich display of Black Opal colors. Crystal Opal is more transparent with deeper tones. White or milky Opals show more diffuse colors. The “Mexican Fire Opal ” is among the most desired. It presents brilliant fire-like colors within its depths. If an opal does not display these color spectrums, it is referred to as “Common Opal “.
Ninety five percent of all fine opals come from the outback deserts of Australia. Opal is the official gemstone of Australia and the province Southern Australia. The Australian Woman’s National team in basketball is called The Opals. Black Opal is the official gem stone for the state of Nevada. Opals are also mined in Mexico, Brazil and in the US, with recent finds in Ethiopia and in the West African country of Mali.
There are many tales and legends about the Opal. They are traced back to the ancient Australian aborigines. Legend says that the creator came down to Earth on a rainbow to bring the message of peace. When his foot first touched the ground, the stones started sparkling in all the colors of the rainbow. This was the birth of the Opal. For ages people have believed in the healing power of the Opal. It is said to cure depression and to help its wearer find true love. Astrologers believe that Opals will enhance the positive characteristics of people born under the zodiac sign of Cancer. Boulder Opal is considered a lucky stone for Aries, and Black Opal is recommended to those born under Scorpio.
A few words of caution about Opals: Opals contain water. If opals are stored in too dry an area or exposed to heat over a period of time, they may become brittle. A decrease in the percentage of water in an opals composition can cause fissures in the stone and decrease its splendid array of colors. Opals should never be placed ultrasonic jewelry cleaners. Opals are a relatively soft stone. They are best placed in a protective setting. Sealing opals with colorless artificial resin has become quite popular to assist in protection. Opal jewelry should be worn as often as possible. This provides the stone with needed humidity from the air and from the skin of its wearer.
When considering purchasing an opal, the following should be assessedOpals should be looked at for thickness, weight, and finish. Fine Opals should be cut and polished to round, oval or dome shape. Only the best quality Fire Opals are suited to faceting.Opals should be looked at for thickness, weight, and finish. Fine Opals should be cut and polished to round, oval or dome shape. Only the best quality Fire Opals are suited to faceting.
Both the presence and pattern of colors are important qualities of opals. If the color red can be seen when looking through the stone, then all the other colors will be present. Other factors affecting the value of an opal are its body color, transparency, translucency or opacity.
Opals should be looked at for thickness, weight, and finish. Fine Opals should be cut and polished to round, oval or dome shape. Only the best quality Fire Opals are suited to faceting.