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. "Natural" opal refers to …

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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 second only …

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.

Aug 28, 2021 · Opals are a hydrated silica gemstone seen in a stunning array of vibrant colors and patterns. Learn why no two opal gemstones are the same, and the meaning, history, and details that …

Jun 20, 2019 · Opals are a unique and mesmerizing gemstone known for their distinctive play of color, making them one of the most sought-after and mysterious gemstones in the world. In this …

Opal [Experiment]

Explore comprehensive opal gemstone information covering varieties like black, fire, and boulder opals, their colors and patterns, historical significance, care tips, and symbolic meanings for enthusiasts …

Common opal is truly amorphous, but precious opal does have a structural element. The word opal comes from the Sanskrit upala, the Greek opallios, and the Latin opalus, meaning "precious stone."