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The Alara Journal
TL;DR: Mastering how to care for opals ensures their brilliant fire and play of color endure for generations. This practical guide breaks down what makes opals geologically distinct, everyday wear habits, safe cleaning protocols, and essential storage advice. Learn why ultrasonic cleaners must be avoided, how to clean opals safely using mild soapy water, and when to bring your jewelry in for a professional checkup.
Few gemstones capture the imagination quite like an opal. Flashing with kaleidoscopic fire, every stone holds its own tiny cosmos. But if you have ever found yourself staring down at a rainbow-hued treasure wondering how to keep that luminous dance alive, you are not alone. Knowing how to care for opals is the secret to enjoying their mesmerizing color play for generations, without stress or guesswork.
Most gemstones you encounter in fine jewelry, such as diamonds or sapphires, are crystalline structures formed under tremendous heat and pressure. Opals take a completely different geological path. They are amorphous hydrated silica, which means they do not have a rigid crystal lattice. Instead, tiny sub-microscopic spheres of silica align in layers, diffracting white light into a breathtaking prism of color.
There are three important gem types that the ancients correctly considered amorphous: natural glass (moldavite and obsidian, among others), amber, and…opal. Opal is truly non-crystalline. It has no predictable internal structure.
In addition to those structural features, another characteristic of opal that is unique in the gem world is its actual chemical composition: SiO₂·nH₂O Hmmmm, do you recognize something in there? Yep, H₂O–-water! SiO₂ is silica. (The “n” is indicating that the quantity of water can vary between 3% and 21%, with most gem-grade varieties containing 5% to 10%.) So opal is actually a hydrated form of silica.
On the Mohs hardness scale, they rate between 5.5 and 6.5. This makes them easier to scratch than quartz, emeralds, or corundum; but more difficult to scratch than a pearl. Think of them less like armor and more like silk: exquisitely crafted, totally wearable, but deserving of a little common sense and conscious love.

Can you wear your opal jewelry frequently? Absolutely. Do you need to adjust your habits so you do not accidentally test geological limits? Definitely. Following simple precautions keeps your gemstone shining brightly.
When it comes to cleaning opals, simpler is always better. You do not need fancy proprietary chemical dips or high-tech equipment. In fact, chemicals and cleaning devices are the quickest route to heartache.

In the case of boulder, nut, and matrix opals, the opal layer is stabilized through the host rock being left intact. So, there’s no cement to concern yourself with. If possible, treat these opals as you would solid opals: by storing such opals and jewelry made with them in distilled water.
Boulder, nut, and matrix opals may be cleaned using the same opal cleaning cycle as solid opals: in warm water and super-mild detergent with a soft cloth. Keep away from household cleaners like bleach and other chemicals. Be sure to rinse off under running water any detergent you do use, and dab dry with a tissue.
In addition to possessing a delicate and thin layer of opal material, opal doublets and triplets also have the additional layer or layers of material affixed to the opal layer. The non-opal materials are never as delicate as the opal itself, so that does not present an additional concern to a solid opal.
But, the cement or glue itself is something that can make caring for an assembled opal a little trickier. There is such a tiny amount of cement used in assembling a doublet or triplet, that just minor effects on it can cause the adhesive to release. So, unfortunately, one should not store an opal doublet or triplet in distilled water. The stability that is gained in having a man-assembled opal means you can’t use the distilled water trick to keep the opal layer hydrated.
It is OK to use a moist towel and mild detergent to clean doublets or triplets, but they should never be submerged or soaked.Be sure to rinse off under running water any detergent you do use, and dab dry with a tissue.
Opals should not be cleaned using standard jewelry cleaner used for diamonds and other non-porous gems.
Because opals contain trapped water, sudden environmental changes can cause issues. Rapid swings from warm room temperatures to freezing conditions, or exposure to bone-dry heat sources, can lead to crazing (fine web-like surface cracking). Here is how to keep your solid opal stable and comfortable:

Even with attentive care, rings experience normal wear over the years. Settings loosen, metals wear down, and stones can gather tiny surface scuffs. Periodic inspection ensures your setting remains secure and the gemstone stays firmly seated.
If your opal has lost a bit of its surface polish after years of faithful wear, do not attempt to polish it at home with abrasive compounds. A skilled jewelry professional can safely inspect the mountings, check prong integrity, and assess whether professional polishing can safely revive that original mirror luster.
Can opals get wet? Solid natural opals are fine with incidental exposure to water, such as washing your hands or walking in gentle rain. However, remove them before swimming in chlorinated pools or bathing, as pool chemicals, salt water, chlorine, and harsh detergents can damage the stone and/or mounting over time.
What is the difference between solid opals and assembled stones? Solid opals consist entirely of natural gem material. Doublets and triplets, however, are layered gemstones where a thin slice of opal is glued to a dark backing (and topped with clear quartz or glass in the case of triplets). Assembled stones should never be submerged in water, as moisture can dissolve or cloud the adhesive layer. Clean doublets and triplets exclusively with a damp cloth.
Why did my opal look cloudy after cleaning? If you used a chemical dip or left a porous variety soaking in tap water, it may have temporarily absorbed liquid or residue. Let it air dry slowly at room temperature away from direct sunlight or heat. Avoid foreign polishes and household chemicals entirely.
For a deeper technical dive on opal quality and durability, the Gemological Institute of America's opal buying guide is an excellent outside resource.
Caring for fine jewelry should feel joyful, not intimidating. Opals bring unmatched character, organic fire, and natural artistry into your daily life. With a tiny bit of mindful attention, your treasured pieces will keep glowing for decades to come.
Have questions about an opal in your jewelry box, or want an expert eye to check your settings? Explore our educational resources, stop by our showroom, or book a friendly consultation with our team at Alara Jewelry. We are always here to help you enjoy every piece you wear.

Written by Babs Noelle, Founder and Graduate Gemologist (GG) of Alara Jewelry, Bozeman, Montana.
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