Last updated: 22 May 2026
At jewellery counters, salespeople often group these five stones as if they were identical. To a casual buyer they do look alike, but they differ sharply in cost, hardness and how long the sparkle lasts.
This 2026 guide rates each stone on hardness, brilliance and cost. Rather than asking which gemstone is 'best', decide what you want the piece to do.
Quick verdict - one line per stone
American Diamond (AD): Best for celebration wear, festive looks and gifting. Plenty of shine without breaking your budget.
Real (mined) Diamond: The premium choice for meaningful keepsakes, where resale value and sentiment matter equally.
Lab-Created Diamonds: Best for engagement rings. A real-diamond look without the mined price.
Moissanite: Best for maximum fire at a fraction of a diamond's cost.
Cubic Zirconia (CZ): Best for fast fashion and stage jewellery where cost per piece rules.
The 5-stone spec table
| Stone | Composition | Mohs hardness | Refractive index | Sparkle character | Price per carat (INR, 2026) | Longevity (daily wear) | Best for |
|---|---|---|---|---|---|---|---|
| American Diamond (AAA CZ) | Zirconium dioxide (ZrO₂), stabilised | 8.0–8.5 | 2.15–2.18 | High white brilliance, soft fire | ₹80–₹300 | 2–5 years on the stone; longer with care | Celebration wear, festive, gifting |
| Real (mined) Diamond | Pure crystalline carbon | 10 | 2.42 | Balanced fire + brilliance, "icy" | ₹85,000–₹3,50,000+ | Lifetime / heirloom | Heirloom pieces, statement solitaires |
| Lab-Grown Diamond | Pure crystalline carbon (CVD/HPHT) | 10 | 2.42 | Identical to mined diamond | ₹25,000–₹75,000 | Lifetime | Engagement rings on a budget |
| Moissanite | Silicon carbide (SiC) | 9.25 | 2.65–2.69 | Very high fire, rainbow flashes | ₹8,000–₹22,000 | Lifetime | Diamond-look engagement rings, statement studs |
| Cubic Zirconia (standard) | Zirconium dioxide (ZrO₂) | 8.0–8.5 | 2.15–2.18 | High brilliance, can dull faster | ₹30–₹120 | 6 months – 2 years on the stone | Trend / fast-fashion pieces |
Hardness uses the Mohs scale of mineral hardness; refractive index is from the Gemological Institute of America (GIA) gemstone database. Prices are 2026 India figures and vary by style and finish.
What Is American Diamond, and Why Is It the Same Family as CZ?
"American diamond" is simply a trade name for cubic zirconia. CZ was first made in a laboratory from synthetic zirconium oxide in the 1970s. The name caught on in South Asian markets in the late 1980s because large CZ shipments arrived from the United States.
Grade is what separates AD from cheap CZ
Grade is what separates AD from cheap CZ. AAA American diamonds are cut with at least 58 facets, match D-E-F colour grades and show no visible inclusions. Lower grades have fewer facets and dull faster. All American diamonds are CZs, but not all CZs meet the AAA standard. Every Nuyug American diamond is AAA.
What Is a Real (Mined) Diamond?
Mined diamonds are pure carbon crystals formed under high heat and pressure deep in the earth. They rank 10 on the Mohs scale, so nothing in everyday use can scratch them.
Mined diamonds are graded on the GIA's 4Cs: cut, colour, clarity and carat.
Price and resale
A 1 carat G colour, VS2 clarity mined diamond costs roughly Rs 1.80-2.60 lakh as a loose stone. You pay for rarity, lineage and resale liquidity; a mined diamond holds much of its value, and large stones can rise as heirlooms. It is a long-term hold, not a short-term trend buy.
What Is a Lab-Grown Diamond?
Lab-grown diamonds are optically and chemically identical to mined diamonds: the same carbon crystal, Mohs 10 hardness, refractive index of 2.42 and fire. The only difference is origin. They take about 4-10 weeks to grow by chemical vapour deposition (CVD) or high pressure/high temperature (HPHT), and are graded by the same labs as mined diamonds (IGI or GIA).
Price and best use
Lab-grown diamonds cost far less than mined stones, typically 80-90% lower for an equivalent size and quality. For an engagement ring you do not plan to resell, a lab-grown diamond is usually the best choice. The secondary market is still young, so if you may want to upgrade in 10 years, a mined diamond suits you better.
What Is Moissanite?
Moissanite (SiC) was first discovered by Henri Moissan in 1893 within a meteorite impact and is now manufactured by scientists within laboratories.
Sparkle
The GIA rates moissanite at 9.25 on the Mohs scale, slightly softer than diamond, with a refractive index of 2.65-2.69 against diamond's 2.42. That higher index gives it more rainbow fire than a same-size diamond. Some buyers love it; traditionalists call it "disco."
Price and best use
In India in 2026, a 1 carat moissanite costs around ₹10,000 to ₹22,000 depending on cut and quality. It is durable and the best of the diamond simulants. Moissanite rings are gaining ground with buyers who want a forever ring without natural-diamond prices.
What Is Standard Cubic Zirconia?
Standard cubic zirconia is mass produced for low-cost fast-fashion jewellery. It uses the same material as American diamond but with less care, so the cut is imperfect and surfaces are rough. Most standard CZ turns cloudy or yellow within 12 to 18 months from sweat, lotion and pool chlorine. It starts at ₹30 to ₹120 per carat.
CZ is not a bad stone for the right job, such as costume or stage jewellery, where cost per piece matters more than longevity. Treat it as a quick buy: wear it, enjoy it, replace it without guilt.
How Do You Choose the Right Stone for Your Use-Case?
- Celebration and occasion wear (festive, gifting): AAA American diamond. Outstanding quality for price, and a piece is easy to refresh between seasons.
- Occasion wear (4-8 times a year): American diamond necklaces, pendants and earrings give the diamond look at no premium.
- Lifetime or daily ring: a lab-grown diamond or moissanite. On a tight budget, start with a solitaire AAA American diamond like the Lumastone Solitaire Ring and upgrade later.
- Legacy or heirloom piece: a real mined diamond. Nothing beats it on resale and sentimental value.
- Gifts: a AAA American diamond solitaire or pendant set looks close to a real diamond and saves a great deal.
How Do You Care for Each Stone?
American diamond: Wash gently every four to five weeks with mild dish soap, cool water and a soft brush. Keep perfume, lotion and chemicals off the stone. Store it in a soft cloth pouch to protect the gold plating.
Real diamond: Safe in ultrasonic cleaners under normal conditions. The only routine maintenance is an annual prong-security check.
Lab-grown diamond: Identical care to a real diamond, including ultrasonic and steam cleaning.
Moissanite: Clean with soap and water. Skin oils dull it faster than a diamond, so clean it at least once a month.
Cubic zirconia: The most scratch-prone of the five. Clean it after each wear and keep it away from pools and showers. Daily wear lasts about 12 to 18 months with regular care.
The bottom line
These stones do not compete; each serves a different purpose. Real and lab-grown diamonds are heirloom stones. Moissanite is the best engagement-ring pick for maximum sparkle at the lowest cost. American diamond is the everyday and party stone you can wear without worry. Standard cubic zirconia is fast fashion.
Decide what the stone has to do, then choose. If the job is "look good, wear it often, cheap to replace," Nuyug's American Diamond collection and ring collection are an excellent place to start.
FAQs
Is American diamond the same as cubic zirconia? Yes - they are the same material (zirconium dioxide). "American diamond" is a trade name used in South Asian markets for higher-grade, diamond-cut CZ. The chemistry is identical; the grade, cut quality, and finishing standards are usually higher in pieces marketed as AD.
Does American diamond look like a real diamond? To the naked eye in good light, yes. AAA American diamond matches a real diamond on whiteness and brilliance. A trained jeweller can tell the difference under magnification by checking facet edges and dispersion, but in everyday wear and photos, the look is convincingly similar.
Does American diamond turn yellow over time? Low-grade CZ can yellow within 12–18 months because of surface contamination. AAA American diamond, properly cared for, holds its colour for years. Yellowing is almost always a cleaning issue, not the stone itself - oils and lotions create a film that reads as warmth.
How long does an American diamond ring last? With basic care, expect 3–5 years of "as new" sparkle on a daily-wear AD ring, and longer on a piece worn occasionally. The gold-plating on the setting usually wears out before the stone does, which is why thick-plating brands offer 1-year warranties on the finish.
Can American diamond pass a diamond tester? No. Standard diamond testers measure thermal conductivity, and CZ conducts heat very differently from diamond. A moissanite-and-diamond combo tester will also flag it as "not diamond." AD is not designed to deceive - it is designed to give the diamond look at a fashion-jewellery price.
Which is better, moissanite or American diamond? They serve different buyers. Moissanite is a lifetime stone with more fire than a diamond; American diamond is a fashion-jewellery stone with diamond-style brilliance at one-fiftieth the price. If the piece is an engagement ring, moissanite. If it is a wedding-guest necklace, American diamond.
Is lab-grown diamond the same as American diamond? No. Lab-grown diamond is real diamond (pure carbon, Mohs 10) grown in a lab. American diamond is cubic zirconia (zirconium dioxide, Mohs 8–8.5), a diamond simulant. Lab-grown is chemically a diamond; AD only looks like one.
How do you spot a fake American diamond (a low-grade CZ being sold as AAA)? Look for sharp facet junctions under a 10x loupe; low-grade CZ has rounded, fuzzy edges. Check for a uniform white return in daylight, not yellowish or grey patches. Reputable brands disclose grade (AAA, AA, A) and offer a written warranty on stone and plating.
