"Precious opal" is the name used for any opal that exhibits "play-of-color". Play-of-color is the familiar flash of bright colorful light that a person sees when viewing opal. Black opal, white …

2024年1月3日 · Common opal is found in many parts of the world, with significant deposits in Australia, Mexico, and the United States. In Australia, it’s mostly found in areas known for …

2021年7月14日 · Precious opal’s ability to show play-of-color is the key difference between precious opal and common opal. Opals are often called chameleon gems because they come …

What's the Difference Between "Common Opals" and "Precious Opals"? Opal is an amorphous form of silica, chemically similar to quartz , but containing 3% to 21% water within its mineral …

Most precious opal is opal-AG. It shows a play of colours ("opalescence") that is due to diffraction of light from the regular packing of submicroscopic silica spheres of roughly equal size (Jones …

Opals displaying play of color are known as Precious Opals, and opals lacking play of color are known as Common Opals. Gems can be cut from both the precious and common forms, but …

Opal is one of the world's most popular gemstones and the birthstone for the month of October. A nice precious opal can flash every color of the spectrum with an intensity and quality of color …

Opal types are primarily based on the gem’s body color. This is the color that shows under a precious opal’s play of color, the flashing or moving colors across its surface. However, …