The internal structure of precious opal causes it to diffract light, resulting in play-of-color. Depending on the conditions in which it formed, opal may be transparent, translucent, or …

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Opal [Experiment]

Mar 5, 2025 · Explore the vibrant world of gemstones! Learn about the different types of opal and where to find them in our comprehensive guide.

Photos of opal from around the world. Guidance for people who want to buy opal, see different types of opal, understand their names, learn about synthetics and imitations.

Opal is the product of seasonal rains that drenched dry ground in regions such as Australia’s semi-desert “Outback.” It is known for its unique display of flashing rainbow colors.

Nov 27, 2025 · Opal, silica mineral extensively used as a gemstone, a submicrocrystalline variety of cristobalite. In ancient times opal was included among the noble gems and was ranked …

Jul 10, 2025 · Opal gems are so unique you’ll need a special vocabulary to describe them. Learn all about the many opal varieties and how to evaluate them.

Aug 11, 2021 · Opal gemstones are hydrated silica crystals that form over millions of years. Learn about opal details, including stone meanings and symbolism, history, pricing, and value.

Oct 1, 2025 · With a rainbow of hues seemingly trapped within, Opal is one of the most colourful of the gems. So, let's find out more about this fascinating beauty.