menu

Home » Gemstones » Opal » Precious Opal

Precious Opal


Pictures of Precious Black Opal and White Opal


Precious opal

Precious opal: Black and white precious opal from Australia.

What is Precious Opal?

Precious opal is a hydrous silicon dioxide material that flashes iridescent colors when it is viewed from different angles, when the stone is moved, or when the light source is moved. This phenomenon is know as a "play-of-color" or an "opalescence." Most precious opals will flash a number of colors such as bright yellow, orange, green, blue, red or purple. Play-of-color is the characteristic of opal that makes it such a popular gem. The desirability of opal is based upon color intensity, diversity, uniformity, pattern and ability to be seen from any angle. In the photo shown here, the stone on the left is a black opal from Lightning Ridge, Australia. The stone on the right is a precious opal from the Coober Pedy, Australia.




More Gemstones
  100+ Gems
  Gem Mineral Collections
  Ruby and Sapphire
  Diamond
  Amethyst
  Emerald
  Pictures of Opal
  Topaz

geology store

More From Geology.com:


minerals
Minerals: Information about ore minerals, gem materials and rock-forming minerals.
Ruby and Sapphire
Ruby and Sapphire are the 2nd and 3rd most popular colored stones in the United States.
Diamonds
Diamonds: Learn about the properties of diamond, its many uses and diamond discoveries.
Geodes
Geodes look like ordinary rocks on the outside but can be spectacular inside!
rocks
Rock Gallery: Photos of igneous, sedimentary and metamorphic rocks.
Fluorescent Minerals
Fluorescent Minerals and rocks glow with spectacular colors under ultraviolet light.
Don't Go To Jail
Know the Rules before removing rocks or minerals from public or private property.
lapis lazuli
Lapis Lazuli - a metamorphic rock and the most popular blue opaque gemstone in history.