Gem of the Week: The Opulent Opal

Queen Charlotte's Opal Ring, 1810
The Royal Collection

Opal is actually a mineraloid composed of a system of small silica spheres which refract the light and cause tension within the stone. The spacing and number of these spheres governs the color of the light which is refracted from the opal. These spheres often exhibit tiny cracks which further change the “color play” (the rainbow effect that the stone demonstrates). Some gem-quality opals are backed with a dark stone material which serves to emphasize the color play.


Opals come in an array of colors and each exhibits unique color refractions. Fire Opal displays warm colors—oranges, yellow, reds and sometimes greens. Often, a Fire Opal is backed in dark stone. Peruvian opals show a blue-green body color. Opals also occur naturally in clear, white, gray, red, orange, yellow, green, blue, magenta, rose, pink, slate, olive, brown, and black. Black opals which exhibit flashes of red are the rarest of these stones.

Opals need special attention. They should not be cleaned in commercial jewelry cleaner as it will dry the stone out. Opals are prone to cracking. The best defense against this is handling your opals. The natural oils in your skin will serve to keep the stones from becoming brittle.

This is a stone with a very mystical quality. Opals have long been regarded as beautiful and they have graced the bodies of people for centuries. Opals reached a peak in popularity in Victorian England and were considered a sentimental favorite. Today, opals are often incorporated into silver jewelry. Their earthy, casual quality suits a variety of occasions.