American Diamond vs Real Diamond: What CZ Is
American diamond is the Indian trade name for CZ (cubic zirconia), a lab-created crystal of zirconium dioxide. It is not a real diamond. CZ looks bright and costs far less than natural diamond, but it is softer (about 8 to 8.5 on the Mohs scale, against 10 for diamond) and can cloud or scratch with years of wear. "Zircon" in jewellery listings usually also means CZ, not the natural mineral.
What is American diamond?
American diamond (AD) is the Indian trade name for cubic zirconia, usually written CZ. It is a lab-created crystal of zirconium dioxide, made to look like a diamond. The name has nothing to do with America, and CZ contains no carbon, which is what a real diamond is made of.
Sellers in India use several names for the same stone: American diamond, AD, CZ, cubic zirconia and, often, just "zircon". The names differ, but the material does not.
| What it is | A lab-created zirconium dioxide crystal |
| Common names | American diamond, AD, CZ, cubic zirconia, zircon (in shop listings) |
| Is it a diamond? | No. It is a diamond simulant, a stone that imitates diamond. |
Zircon or CZ: are they the same?
Not quite. Natural zircon is a natural mineral (zirconium silicate) that forms in rock. Cubic zirconia is a different material made in a lab. In jewellery listings, "zircon" almost always means CZ rather than natural zircon.
So if a ring or pair of earrings is listed as zircon, ask the seller whether the stone is CZ or the natural mineral. Either way, it is not a diamond.
CZ, lab-grown diamond and natural diamond
Lab-grown diamond is real diamond. It is carbon with the same crystal structure as a mined diamond, grown in a lab instead of in the earth. CZ is a different material altogether. The table compares the three.
| CZ (cubic zirconia) | Lab-grown diamond | Natural diamond | |
|---|---|---|---|
| What it is | Lab-created zirconium dioxide crystal | Real diamond (carbon), grown in a lab | Real diamond (carbon), formed in the earth |
| Hardness (Mohs) | About 8 to 8.5 | 10 | 10 |
| Scratch and wear | Can scratch and cloud over years | Very hard, resists scratching | Very hard, resists scratching |
| Coloured flashes | Strong, more coloured fire | Brilliant white light | Brilliant white light |
| Price level | Low | Mid, well below natural | High |
| How to label it | CZ (cubic zirconia), lab-created | Lab-grown diamond | Natural diamond |
Hardness is the main practical gap. Diamond is 10 on the Mohs scale, the hardest natural material. CZ is about 8 to 8.5, so its facets can pick up fine scratches, and over years of daily wear it can lose its polish and look cloudy. A CZ ring worn every day will keep its best look for a shorter time than a diamond one.
For the same size, CZ is also much denser than diamond, so a CZ piece feels heavier in the hand. CZ throws more coloured flashes of light than diamond, which is why it can look very sparkly in a shop. That rainbow flash is a clue, but it is not proof on its own.
How to tell CZ from a real diamond
The reliable test is a diamond tester, a small electronic probe that measures how quickly heat passes through a stone. Diamond conducts heat very quickly and CZ does not. Most jewellers in India have one, and the test takes seconds. Ask the jeweller to test the stone itself and to write the result on the bill.
Home tests that circulate online are not reliable. Breathing on a stone to see how long the fog lasts depends on the room and the surface of the stone. A scratch test can mark the stone itself. Do not use either to decide whether a stone is a diamond.
A proper bill names the stone. "CZ (cubic zirconia), lab-created" is the clear and honest wording. Be cautious of any bill that says only "diamond" for a stone sold at a CZ-style price.
Caring for CZ jewellery
- 1Clean gently
Wash in lukewarm water with a drop of mild soap, and brush softly around the setting with a soft brush.
- 2Rinse and dry
Rinse well and pat dry with a soft cloth so no soap stays behind the stone.
- 3Store it apart
Keep CZ pieces in a soft pouch, away from harder jewellery, so the facets do not scratch.
- 4Take it off first
Remove CZ before perfume, lotion, swimming and harsh cleaning products.
Among anokhi pieces with CZ stones are the 925 Silver Half-Eternity Band · CZ (₹2,998), the Rose Gold-Plated 925 Silver Ring · Solitaire-Look CZ (₹3,198) and the 925 Silver Necklace & Stud Earring Set · CZ (₹4,598).
anokhi uses CZ in some of its pieces and always labels it CZ (cubic zirconia), never diamond, so you know exactly what you are buying.
Frequently asked
Last reviewed: 17 May 2026 · Verified by the anokhi expert panel
What is American diamond?
American diamond is the Indian trade name for CZ (cubic zirconia), a lab-created crystal of zirconium dioxide. It is a diamond simulant, not a real diamond. It looks bright and costs far less than natural diamond, but it is softer and can cloud over time.
Is American diamond a real diamond?
No. Real diamond is carbon, while American diamond is CZ, a different lab-made material. The real-diamond option made in a lab is lab-grown diamond, which is carbon and is sold as diamond.
Is zircon the same as CZ?
Not exactly. Natural zircon is a natural mineral, while cubic zirconia is lab-made. In jewellery listings, zircon usually means CZ, so ask the seller which one you are getting. Neither is a diamond.
How do I tell CZ from a real diamond?
A diamond tester that measures how fast heat passes through the stone is the reliable check, and most jewellers in India have one. Breath-fog and scratch tests are not reliable. Ask for the stone to be tested and named clearly on the bill.
Is CZ jewellery worth buying?
CZ suits people who want a bright, affordable stone for everyday or occasion wear and know that it is not diamond. It does not hold resale value the way natural diamond can. Treat it as fashion jewellery and look after it with gentle care.
Does CZ tarnish?
The CZ stone itself does not tarnish. The silver setting can tarnish over time, as all 925 silver does, so store it dry and airtight and clean it gently. Tarnish on the metal is normal and wipes off.
Can CZ get scratched?
Yes. CZ is softer than diamond, at about 8 to 8.5 on the Mohs scale, so its facets can pick up fine scratches. Store CZ pieces separately from harder jewellery and avoid rubbing them on rough surfaces.
Reviewed by the anokhi silver desk
Written and reviewed by anokhi's in-house silversmiths. Every piece we make is 925 sterling silver, BIS hallmarked and handcrafted in Jaipur. Last updated 11 October 2026.