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 …

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.

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 …

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.

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.

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 …

Jul 28, 2025 · Opal forms here through a fascinating natural process. When water containing silica seeps into cracks and voids in rocks, it begins to evaporate, leaving behind tiny silica spheres. Over …

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Detailed gem and jewelry information guide about the gemstone opal, including black, white, boulder, and precious.

Feb 7, 2025 · Opals come in a variety of hues and types, each with its own geological formation process and cultural significance. In this article, we will explore the science behind opal formation, its different …