How Is Opal Formed?

Have you ever wondered about the science behind the splendor? How those incredible shifting rainbows are created inside of stone? Opals are formed from a mineral known as silica, specifically hydrated amorphous silica. Silica is a common mineral found in soil, sand, granite, concrete, rock, and many other natural materials. Hydrated amorphous silica simply means that opal has a high water content.

Opal is found in many places like Brazil, Mexico, Honduras, and the Western US, however Australia produces 95% of the world’s precious opal. NIXIN Jewelry sources nearly all of our precious opal from Australia, working with material like boulder opal from Winton, Queensland to crystal opal from famed Lightning Ridge and from Coober Pedy, the Opal Capital of the World.

How does opal form?

Opal is found deep in the Earth’s crust near faults, cracks, or fissures. It is believed that around 30 million years ago a large amount of silica was released and filled in these cracks. In fact, fossil evidence suggests that Australia used to be under the ocean. Some of those fossils were replaced by silica and formed what we call Shell Opal and Opalized Belemnites (ancient squid-like creatures).

Image of opalized belemnite
Opalized Belemnite, Photo by James St. John

Like ocean water, rainwater also contains small amounts of silica (among other minerals) and collects more as it falls onto soil, sand, granite, and concrete. Over time the silica, which has a spherical chemical structure, settles into perfectly stacked spheres along these fissures. This symmetrical, three-dimensional array creates diffraction and interference, which is what produces the brilliant opal colors we all know and love. The range of colors depends on the size of the silica spheres as well as the refraction at the surface of the opal. A mere 1cm of opal can take up to 6 million years to form; though slow to grow, the resulting myriad of colors is breathtaking.

Opal Ring

Opal & Sapphire Ring

How is opal mined?

While a range of mining methods are employed, much opal is mined by shaft sinking or shaft mining, which means a vertical tunnel is excavated from the top down until some promising “opal dirt” is discovered. Once opal is discovered, a miner then slowly branches out sideways using a hand pick or screwdriver to carefully extract any opal they found. Opals are delicate gemstones, and should be handled with care from extraction and transporting to designing and wearing, but when cared for properly, they can last a lifetime.

NIXIN Jewelry has relationships with opal suppliers across the globe, working directly with the miners who extract this spectacular material from the earth, as well as with the talented artisans who cut these beautiful gems, revealing the colorful secrets within. When you purchase opal jewelry from NIXIN Jewelry, you can feel confident knowing you are supporting a network of small businesses and skilled artisans around the world who love what they do.

If you’re looking for a one-of-a-kind piece of art that evokes emotion and tells your unique story of strength, perseverance, or love let NIXIN Jewelry guide you through our selection of precious opal rings for women. Nicki, Founder and Designer of NIXIN Jewelry, selects only the most striking opal gemstones and transforms them into spellbinding visuals meant to awaken your soul. Each opal ring is dressed in 14K gold and paired with carefully curated precious gemstones like diamonds, sapphires, and emeralds that echo the translucent shades of the opal.

NIXIN Jewelry offers a stunning, bespoke collection of handcrafted Australian opal rings, opal necklaces and opal earrings in an array of sizes and styles.

Visit our shop to start living your life—in color.

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