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 polished stones consisting wholly of precious opal. Opal is a fascinating mineral known for its unique play of colors and diversity.

Understanding the Context

There are many types of opal, each with distinct characteristics that make them special. For example, boulder opal, hyalite, and fire opal are all unique forms of this mineral. Opal makes it easy to create multi-step flows that chain prompts, model calls, and tools together. Simply type what you want to make with natural language and Opal builds a workflow you can...

Key Insights

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. 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 to emerald by the Romans.

Final Thoughts

October’s birthstone, opal is a gem of positive transformation, revealing the colorful attributes of those who wear it. Magical, mysterious, and lively—opal is captivating new admirers with its variety. Opal is a mineraloid composed of silica and water. Most opals you’ll come across are 6-10% water. Stable opals can have as low as 3% water content and as high as 21%. Under a microscope, opal contains stacks of hydrated silica spheres aligned together like a Buckyball cube.