Opals

Among the ancients, Opal was a symbol of fidelity and assurance and in later history it became strongly associated with religious emotion and prayer.  It was believed to have strong therapeutic value for diseases of the eye, and, worn as an amulet, it would increase the powers of the eyes and the mind.  Also, to the degree that the stone exhibited the colors red and green, from Ruby and Emerald, the wearer would also enjoy the therapeutic powers of those two stones: from the Ruby the ability to stop bleeding and from the Emerald the ability to cure kidney disease.

How appropriate that this stone that so brilliantly portrays the colors of Autumn should be the birthstone for October!  Its colors are the result of hydrated silica spheres - think of them as perfect little spheres of water - trapped in an almost clear matrix of rock.  Like water spheres suspended in the air that create rainbows after a rain, these break down light into its component colors and create perfect tiny rainbows in each stone.

Opals occur around the world, with the most famous deposits being located in Australia.  Opal occurs in several varieties and appears in jewelry stores under several names, which can become confusing.

Boulder Opals are pieces of Opal still attached to the dark colored rock on which they were originally formed in the earth, giving depth and contrast to the Opal's iridescence.  Sometimes this is reproduced, adhering a thin layer of Opal onto a dark colored stone to create what is called a "Doublet".

Black Opals are extremely rare and valuable!  Instead of the matrix being a pale white color, it is almost black, which makes the colors appear even brighter and more spectacular.

Mexican Fire Opals are indigenous to Mexico and come in a variety of hues that range from salmon pink to brilliant red.  Their unique color offsets the fact that they don't generally exhibit the spectral colors to the same degree that other Opals do.

Opals are quite a soft stone and require some special consideration.  Keep your Opals away from other gemstones in your jewelry box because they are easily scratched.  Being nice to your Opals includes giving them a quick wipe with a good quality oil - like olive oil - every once in a while.  Like the process of oiling Emeralds, this will fill in the tiny scratches and imperfections on the Opal's surface that affect its brilliance and fire.  Do not soak your Opals, this will destroy the color within.

Things to look for:

The value of Opals, as with all colored gemstones, rises as the colors get more intense.

Reds and Greens are the most desireable colors.

There are very attractive synthetic Opals on the market, the most common of these is called a "Gilson Opal".