What Is Cubic Zirconia? And Why We Set It in Almost Everything We Make

Almost every question we get about our pieces turns into the same question eventually: what are the stones?

In nearly everything we make, the answer is cubic zirconia. So here is the whole thing, plainly: what it actually is, how it behaves next to a diamond, why we choose it, and what separates the good version from the version that looks flat within a month.

So What Is Cubic Zirconia, Exactly?

Cubic zirconia is a crystal grown in a lab from zirconium oxide. The powder is melted at around 2,700°C and cooled slowly until it forms in a cubic crystal structure, which is where the name comes from. That structure is the entire point. It is what makes the material colorless, hard enough to hold a sharp facet, and cuttable like a gemstone rather than moldable like glass.

Two things it is not. It is not glass or leaded crystal, which are pressed or molded, sit much lower on the hardness scale, and cloud quickly at the edges. And it is not a diamond, which is carbon, and which we are not going to pretend otherwise about.

It is worth knowing that cubic zirconia wasn't invented to imitate anything. It was developed in the 1970s for laboratory optics, and the jewelry industry took it because the crystal turned out to be beautiful.

How It Behaves Next to a Diamond

The honest read of that table: cubic zirconia throws more rainbow than a diamond does. Fire is the measure of how much a stone splits white light into color, and CZ scores meaningfully higher. What a diamond wins on is the white sparkle, which comes from that higher refractive index, and hardness, which is a durability story rather than a beauty one.

The giveaway is weight. Pick up a cubic zirconia stone next to a diamond of the same size and the CZ is noticeably heavier. That is how a jeweler knows in about a second, and it is a more reliable tell than anything you can see.

A tip, while we are here

The two look close enough that some dealers will try to pass cubic zirconia off as a diamond. So if you are ever buying an actual diamond, from anyone, always get the certificate. A grading report from a recognized lab is the only version of that conversation that isn't just trust.

Why We Use It

It Lets Us Design Generously

This is the real reason. Stone size is the single most expensive variable in fine jewelry, so designing around mined stones means designing small. Cubic zirconia takes that constraint off the table entirely, which is how a piece like the Ayla Chandelier Earrings can be set with stones all the way down its zigzag and still cost $140.

The same logic gives you the upward spiral of the Zahra Earrings and the full stone-set band of the Lustra Hoop Earrings. Those designs only exist because the stones are lab-grown.

The Stones Match, Every Time

Mined stones vary. Two of them cut from different rough can sit next to each other in the same earring and read as slightly different colors, which is why matched sets get expensive fast. Cubic zirconia is grown to a consistent formula, so a pair of earrings looks like a pair, and the piece you order in March matches the one you order in November.

It Puts the Money Where You Feel It

Spending less on stones means spending more on everything you actually touch. That is 925 sterling silver posts, thicker plating that survives real wear, and settings that hold each stone in metal prongs rather than a bead of glue. On a $70 to $170 piece, that is where the difference between something you keep and something you replace actually lives.

Nothing Came Out of the Ground

Every stone we set was grown in a furnace. That matters more than it sounds like it does.

A mined stone starts with a mine. Diamond recovery means moving an enormous quantity of rock and earth for every carat that comes out of it, along with the water use, the land disturbance, and the tailings that go with any operation at that scale. Then there is the chain of custody, which is the part nobody can fully show you: where the stone came from, who handled it, and whether the paperwork tracked the actual rough or just resembled it.

Cubic zirconia skips that entire chapter. No pit, no tailings, no waterway, no origin question, and no supplier whose word you have to take.

We are not going to tell you it is impact-free. Growing crystals at 2,700°C takes real energy, and pretending otherwise would be the kind of thing this whole post is trying to avoid. But it is a furnace and a formula rather than a landscape, and that is a meaningfully different footprint.

There is a quieter version of this argument too. The most wasteful jewelry is the piece that falls apart and gets thrown away, and the greenest thing any of it can do is stay in rotation. A well-cut stone in a properly plated setting is a piece you are still wearing in five years instead of the third replacement for something that went green at the edges.

Not All Cubic Zirconia Is the Same

This is the part most brands skip, and it is the part that actually decides how a piece looks on you.

Every piece we sell is designed and curated by my mother, who has been a certified gemologist for twenty years. Twenty years of grading real diamonds, which means twenty years of knowing precisely what separates a high-quality stone from a low-quality one. That eye does not switch off when the stone is cubic zirconia. The same grading instinct is what decides which stones go into our pieces and which ones get sent back.

You can see the difference without any training at all. Turn a good stone in the light and it comes alive, refracting light from every facet, looking like something that cost more than it did. Turn a cheap one and it just sits there. Flat, slightly gray, obviously inexpensive. Same material, entirely different result.

What actually creates that difference

The cut. Facets should meet in crisp points, and the stone should sparkle from across a room rather than only under a lamp. Precision cutting is the first cost a manufacturer drops, and it reads immediately as a dull, slightly milky stone.

The setting. Prong-set and channel-set stones are held by metal. Glue-set stones lift at the edges, catch dirt underneath, and eventually fall out. Turn a piece over. You can usually see which one you are looking at.

The metal underneath. A well-cut stone in cheap base metal will outlive its own setting. The piece tarnishes green, the plating rubs through, and the stone is the only part still working.

The match. In a multi-stone piece, check whether every stone reads the same brightness. Mixed grades in one design are a sign of stones bought by the bag rather than specified.

All of our cubic zirconias are selected by our creative director and designer, Mamta Valrani. She has been a certified gemologist for 20 years and uses her wealth of experience and trained eye to only select the best of the best for our pieces.

How to Keep Yours Sparkling

Cubic zirconia doesn't fade or lose color. What actually dulls it is a film of lotion, hairspray, and skin oil sitting across the facets, and that comes off.

• Put your jewelry on last, after perfume, lotion, and hairspray have dried.
• Take it off before swimming, showering, or the gym. Chlorine and salt are hard on plating, and plating is the vulnerable part.
• Clean with warm water, a drop of mild dish soap, and a soft toothbrush around the settings. Rinse and dry completely.
• Skip ultrasonic cleaners and anything abrasive. They are rough on plating and on glue-set stones.
• Store pieces in their pouch rather than loose in a dish, so stones don't scratch against each other.

That routine takes two minutes and restores essentially all of the sparkle.

Common Questions About Cubic Zirconia

Is cubic zirconia fake?

It is a real, lab-grown crystal with its own optical properties. It is a simulant, which means it is designed to resemble a diamond without being one. That is different from an imitation stone like glass, which has no crystal structure at all.

Is cubic zirconia more sustainable than a mined diamond?

It is grown in a lab, so there is no mine, no tailings, and no origin question attached to it. That removes the largest environmental and ethical costs in the diamond supply chain. It isn't impact-free, since growing crystals takes significant energy, but the footprint is a furnace rather than a landscape.

Does cubic zirconia get cloudy over time?

The stone doesn't change. What clouds is the buildup of oils and product on the surface, and a warm soapy wash takes it off. Cloudiness that survives a proper cleaning usually means the facets were abraded by an ultrasonic cleaner or an abrasive polish.

Can you wear cubic zirconia every day?

Yes. The stone handles it easily. The thing to protect is the plating on the metal, so take pieces off for swimming and the shower and you'll get years out of them.

How can you tell cubic zirconia from a diamond?

Weight is the fastest tell, since CZ is about 1.6 times heavier for the same size. Cubic zirconia also throws noticeably more rainbow color, where a diamond returns more white light. A jeweler's thermal tester settles it in seconds, and a grading certificate settles it before you pay.

Is cubic zirconia jewelry hypoallergenic?

The stone itself is inert and doesn't cause reactions. Whether a piece is hypoallergenic comes down to the metal, not the stone used in it.  materials.

The Stones Are Only Half of It

A good stone in a bad setting is a piece you stop wearing. What we care about is the whole thing: the cut of the stone, the metal holding it, and whether the design is worth putting on in the first place. That is why the stones get graded by someone who spent twenty years grading diamonds, and why they look expensive.

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