Shopping for an opal ring to celebrate an October birthday? The multi-colored opal is the birthstone for those born in October. When moved to reflect the light, opals give off a rainbow of colors. When it comes to opals, most people think of the lighter version before considering the stone's two other cousins, the fire opal and the black opal.

The fire opal reflects light and gives off color much like the traditional multi-colored opal. However, the fire opal glows with orange and red hues as opposed to the traditional pastel colors. The fire opal makes a wonderful alternative when purchasing earrings, bracelets or an opal ring.

The most expensive and rare of opals is the black opal. These stones can range in color from gray to black and reflect elegance and wealth when worn on the ears, neck or fingers. Since the opal only reaches five or six on the Mohs Scale, opals must be specially cared for. Ultrasonic cleaners and oils should never be used on an opal. You may want to consider bringing your opal into a professional jeweler to have it cleaned.

Australia is the world's leading location for opal mining. New South Wales, South Australia and Queensland mine about $500 million worth of opals every year. While other areas around the world (Nicaragua, Soviet Union, Brazil, Africa and the U.S.) have some areas fruitful in opal mining, most of these precious stones come from the land down under, while Mexico is largely responsible for the fire opal.