Best Fake Diamonds (2026): 5 Options Ranked for Chains

The best fake diamonds are moissanite for most people, cubic zirconia (CZ) if price matters most, and lab-grown diamond if you want an actual diamond without the mined price. Moissanite is the only simulant that is harder than 9 on the Mohs scale, throws more sparkle than a diamond and reads as a diamond on most handheld thermal testers. CZ looks close on day one but is softer and costs a fraction of the price.

We sell all three at Adamans, so we have no reason to push one stone over another. This guide ranks five options on the numbers that decide how a stone looks and lasts: hardness, brilliance, fire, tester results and price. It's written for chains, bracelets and men's iced jewelry, not just engagement rings, which is what most other lists cover. Prices are our live prices as of November 6, 2026.

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Best fake diamonds ranked

Here is the short version. "Fake diamond" covers two different things: simulants, which only look like diamond (moissanite, CZ, white sapphire, glass), and lab-grown diamonds, which are diamonds made in a factory instead of a mine. We include lab-grown because people search for it under the same name, but it belongs in its own class.

How fake diamonds compare: hardness, sparkle and testers

Three numbers explain almost everything. Hardness (Mohs scale) decides how well a stone resists scratches. Refractive index decides brilliance, the white light coming back at you. Dispersion decides fire, the flashes of color. A diamond tester adds a fourth check that matters if you care about passing one.

These are standard gemological reference values. The moissanite figures come from GIA's original 1997 Gems & Gemology report on synthetic moissanite, and the sapphire hardness from GIA's sapphire page.

Read the table this way. Moissanite has a higher refractive index and more than double the dispersion of diamond, so it is brighter and more colorful, not less. CZ sits just below diamond on brilliance, which is why it looks so good in a store. White sapphire is hard, but its low refractive index means it returns much less light.

1. Moissanite: the best fake diamond overall

Moissanite is lab-made silicon carbide. It is the closest thing to diamond you can buy without buying a diamond, and it is the stone in most of our best sellers.

Why it wins

• Hardness 9.25. Only diamond is harder among common jewelry stones. On a tennis chain that rubs on shirts and zips every day, that matters more than on a ring kept in a box.
• Brilliance and fire. It returns more light than diamond. Under club or phone lights that reads as more ice, not less.
• Testers. Moissanite conducts heat like diamond, so it reads as diamond on most handheld thermal testers. A multi-tester that also checks electrical conductivity can tell them apart. We cover this in detail in does moissanite pass a diamond tester.
• Grading. Good moissanite is graded on color and clarity like diamond. Ours is D color VVS1 moissanite, and every piece in our moissanite line comes with a GRA report.

Where it falls short

Moissanite's extra fire is the honest catch. In direct sun, larger stones throw more rainbow flashes than a diamond would. Most people never notice on 3mm to 5mm stones. On a single big solitaire, a trained eye can. Lower-grade moissanite can also show a faint yellow or gray tint, so check the color grade before you buy.

What it costs

As of November 6, 2026, our 5mm Moissanite Tennis Chain - Silver - D Color - VVS1 is $449.99 to $469.99 depending on length. The 3mm version is $349.99 to $386.99, and the 10mm Moissanite Clustered Tennis Chain - Silver - D Color - VVS1 is $769.99 to $799.99. The product pages list the metal as 18K white gold plating.

2. Lab-grown diamond: not fake, just not mined

A lab-grown diamond is carbon in the same crystal structure as a mined diamond. Same hardness, same refractive index, same tester result. In 2018 the US Federal Trade Commission dropped "natural" from its definition of a diamond, so lab-grown stones count as diamonds, as long as the seller clearly says they are lab-grown (Rapaport's report on the FTC change).

So why is it on a list of fake diamonds? Because many shoppers search that way, and because it is the option to pick if "fake" is the part that bothers you. You get a grading report (ours are IGI) and a stone no tester will flag.

The catch is price. Our IGI lab-grown diamond tennis chains start at $3,130.99 for the 3mm chain as of November 6, 2026, and they are made to order. A 3mm moissanite chain is $349.99. For a full tennis chain, that gap is the whole decision for most buyers. Our moissanite vs lab diamond comparison goes deeper.

3. Cubic zirconia: the best cheap fake diamond

CZ is lab-made zirconium oxide and a very common diamond simulant. Brand new and clean, a well-cut CZ looks very close to diamond from a normal distance.

The trade-offs

• Softer. At 8 to 8.5 on the Mohs scale it picks up fine scratches over time, and scratched facets look cloudy. Chains take more knocks than most jewelry, so expect this sooner.
• Fails a diamond tester. CZ does not conduct heat like diamond, so a thermal tester will flag it straight away.
• Heavier. CZ is denser than diamond, so a CZ chain of the same size feels a little heavier.

It is the right pick if you want the look for a lower price, or want to try a width or style before spending more. Our cubic zirconia chains are a separate, cheaper line. As of November 6, 2026, the 4.5mm Tennis Chain - White Gold in that line is $99.99. We never sell CZ as moissanite. Every product title tells you which line you are looking at. For a straight head-to-head, read moissanite vs cubic zirconia.

4. White sapphire: hard but flat

White sapphire is colorless corundum, the same mineral as blue sapphire. At 9 on the Mohs scale it is tough, and it can be natural or lab-made.

The problem is sparkle. With a refractive index around 1.77 and very low dispersion, it returns much less light than diamond or moissanite and shows almost no fire. In small stones on a chain it can look glassy. It also fails a thermal diamond tester. It makes sense for someone who wants a natural gemstone and a softer, quieter look. For iced chains it is a poor fit, which is why few brands use it there.

5. Crystal and glass: costume only

Leaded crystal and glass are among the lowest-cost stones in fashion jewelry. They can look bright under shop lights, but at around 5 to 6 on the Mohs scale they scratch from everyday dust and lose their edge fast. They fail every diamond test. Fine for a costume piece or a one-night outfit, not for something you wear daily.

Best fake diamonds for chains and men's jewelry

Most "best fake diamond" lists are about engagement rings. Chains are different. A tennis chain has dozens to hundreds of small stones, sits against fabric and skin all day, and gets judged at arm's length, often under strong light. That changes the ranking a little:

• Hardness matters more. Every stone takes wear. Moissanite and diamond hold their polish. CZ is the one that dulls first.
• Fire matters less. Moissanite's extra rainbow is hard to spot on 3mm to 6mm stones. It shows on big single stones, not on a row of small ones.
• The setting and metal matter as much as the stone. Check the prong or box setting, the clasp and the plating. A great stone in a weak setting still falls out.
• Price scales with stone count. A lab-grown diamond chain carries dozens of carats, which is why the price jumps so far past moissanite.

How to tell which fake diamond you are buying

1. Read the stone name. A trustworthy listing says moissanite, cubic zirconia, lab-grown diamond or white sapphire. "Iced", "VVS stones" or "diamond look" are not stone names.
2. Ask for the report. Moissanite usually comes with a GRA report. Lab-grown diamonds come with IGI or GIA reports. CZ and glass have none.
3. Use a thermal tester. Diamond and moissanite pass. CZ, white sapphire and glass fail.
4. Look at the fire. Strong rainbow flashes in sunlight point to moissanite. Bright white with some color points to diamond or CZ. Little sparkle at all points to sapphire or glass.
5. Check the price. A full tennis chain of real or lab-grown diamonds for a few hundred dollars does not exist. Price tells you a lot.

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Best fake diamonds: common questions

What is the best fake diamond that looks real?
Moissanite. It is harder than every other simulant, returns more light than diamond and reads as diamond on most thermal testers. Cubic zirconia looks close when new but dulls sooner.

Which fake diamonds pass a diamond tester?
Moissanite passes most handheld thermal testers because it conducts heat like diamond. A multi-tester can tell them apart. Cubic zirconia, white sapphire and glass fail, and lab-grown diamonds pass because they are diamonds.

Is moissanite a fake diamond?
Moissanite is a diamond simulant, not a diamond. It is its own gemstone, silicon carbide, with different properties. It is sold as moissanite, not as diamond.

Are lab-grown diamonds fake?
No. Lab-grown diamonds are carbon with the same structure and properties as mined diamonds, and the FTC counts them as diamonds. Sellers must clearly say they are lab-grown.

What is the cheapest fake diamond that still looks good?
Cubic zirconia. A well-cut CZ looks close to diamond when clean and new. Expect it to scratch and cloud faster than moissanite with daily wear.

Do fake diamonds get cloudy?
Softer stones do. Cubic zirconia and glass pick up surface scratches that make them look cloudy over time. Moissanite and diamond hold their polish, though any stone looks dull when dirty and comes back with cleaning.