For use in jewellery, most opal is cut and polished to form a cabochon, a convex shape that maximises the viewing angles through which an opal's play of colour can be observed. …

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.

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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 …

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.