A Matter of Brilliance is a professional jewelry appraisal company based in Newton, MA, founded by Aimee Berrent, Graduate Gemologist. Our appraisals can be used to:
October birthday girls (and boys), opals, your birthstone is a magnificent gem that defines “play of colors.” As the fall brings muted colors and less daylight, the opal defies that to bring fire and splashes of color.
The American Gem Society notes that the name, opal, “comes from the Greek Opallos, meaning “to see a change (of color).” Opals range in color from milky white to black with flashes of yellow, orange, green, red, and blue.” Precious opals are found most often in Australia—90% of the world’s reserves.
What gives opals their glow
Opals are formed when silica gel seeps into stone crevices. When it goes through eons of heating, molding, and cooling, the gel hardens into the opals that we recognize.
Opals in jewelry
Opals have a hardness of about 5.5-6.0 on the Mohs hardness scale. That makes it on the softer side of gemstones. Because of this, you should be careful having opals in rings—bezel cuts that protect the stone are useful. But opals work very well in earrings and brooches that don’t get banged on counters and other surfaces.
Opals and “play of color”
There are common opals that are milky. However, when we think about opals, we often refer to those specimens that have beautiful flashes of color. These are referred to as “play of color.” These are referred to as “precious opals.” This well-known flash of color is formed by microscopic pieces of silica. As light passes through the array, it becomes diffracted into different colors of the spectrum.
Happy birthday, October birthday girls and boys. Enjoy your beautiful birthstone with its fire, luminescence, and light.
If I can help you with your opals or any other gemstones, let me know.