Are Lab Diamonds Real Diamonds? Yes, and Here Is the Proof

A lab-grown diamond is not fake, not a simulant and not "almost a diamond." It is diamond, grown above ground instead of mined. GIA states that laboratory-grown diamonds have essentially the same chemical, optical and physical properties and crystal structure as natural diamonds. The US Federal Trade Commission removed the word "natural" from its definition of diamond in 2018, so a lab-grown stone fits the legal definition too.

Where people get confused is the word "real." In everyday speech it means "not fake," and in that sense a lab diamond is real. In FTC marketing rules, "real" is one of the words a seller may not use to describe a lab-grown diamond, because it can imply mined origin. Both things are true at once: the stone is genuinely diamond, and the seller has to say it was grown in a lab.

The fastest way to see why a lab diamond is real is to put it next to the stones that are actually imitations.

The lab-grown column matches the natural column line for line except origin. Moissanite and cubic zirconia are different materials that imitate diamond; they are covered in how to spot fake diamonds.

Handheld diamond testers work by measuring how fast heat moves through a stone; diamond conducts heat extremely well. A lab-grown diamond conducts heat exactly like a mined one, so it reads as diamond. Multi-testers add an electrical conductivity check to catch moissanite, which can fool a heat-only tester. Lab-grown diamonds pass that test too.

One quirk: a small number of diamonds, natural or lab-grown, contain boron, which makes them conduct electricity. Those rare stones can trigger a "moissanite" warning on some multi-testers. It is the exception, not the rule, and a lab can settle it. What no tester does is tell lab-grown from natural. For that you need a gem lab.

Diamonds have been grown in labs for about 70 years. General Electric reported the first reproducible synthesis using a high-pressure, high-temperature press in the 1950s; those early crystals were small and used in industry for cutting and grinding. Gem-quality lab-grown crystals followed in the early 1970s, but they were costly and rare. Only in the last decade or so did CVD and improved HPHT methods make colorless, multi-carat lab diamonds common in jewelry stores.

That history explains the confusion. For most of the 20th century "synthetic" meant industrial grit or an imitation stone. The word followed lab diamonds into jewelry even after the stones became gem quality, and the FTC now discourages using "synthetic" in a way that suggests a lab diamond is not a diamond.

Since the material is the same, labs identify origin through how the crystal grew. Natural diamonds grew slowly under varying conditions and carry nitrogen patterns and mineral inclusions from the earth. Lab-grown stones show growth patterns typical of HPHT presses or CVD reactors, sometimes with tiny metallic inclusions (HPHT) or layered growth lines (CVD). Labs read these clues with spectroscopy and ultraviolet imaging that ordinary jewelers do not have.

When a lab grades a lab-grown diamond, it usually laser-inscribes the girdle with the report number and a note that the stone is lab-grown. That is the most practical proof of origin for an owner. Read more in our complete lab-grown guide and the certificates guide.

To read an inscription yourself, hold the ring under a bright light, tilt it so the girdle (the thin outer edge of the stone) faces you, and look with a 10x loupe. You will see a short string of tiny letters and numbers. Type the number into the lab's online report check and compare the weight and measurements with your stone. If they match and the report says laboratory-grown, you have both proofs at once: it is diamond, and it is lab-grown.

Authenticity also shows up over years of wear. A lab-grown diamond scores 10 on the Mohs scale, so it resists scratches like any diamond. It does not cloud, fade or change color. Cubic zirconia, by contrast, scratches and turns hazy within a few years of daily wear, and moissanite, though very hard at 9.25, shows its stronger rainbow fire from day one. If a "diamond" gets cloudy and scuffed on its facets after a year or two, it was not a diamond. A lab-grown diamond simply looks the same as the day you bought it, once it is cleaned.

The FTC Jewelry Guides set the language sellers in the US may use. In plain terms:

Trade press summaries of the 2018 revision note that the FTC dropped "natural" from the definition of diamond while keeping strict disclosure duties. The rule protects both sides: buyers of mined diamonds know they are getting mined stones, and buyers of lab-grown diamonds know they are getting real diamond at a lab-grown price.

A simulant is any material that imitates diamond without being diamond. The two common ones in jewelry today are moissanite and cubic zirconia. Both can look convincing in photos and both are often sold under vague names like "VVS stones" or "iced." The differences show up in testing and over time: cubic zirconia scratches and gets cloudy with wear; moissanite throws strong rainbow flashes and has double refraction that a loupe can reveal from certain angles.

A lab-grown diamond is not on that list. It is the material those stones imitate. If a seller lumps lab diamonds in with simulants, they are either confused or trying to sell you something else.

Being real does not make a lab-grown diamond equal in value to a mined one. Lab-grown prices keep falling as production improves, so resale is low, while natural diamonds keep more of their value even in a soft market. That is the honest trade: a lab diamond gives you the real material and the real look for far less money, and a natural diamond gives you rarity and some resale. Knowing which one you are buying, in writing, is what the FTC rules are there to guarantee.

The doubt is understandable. For decades "synthetic" meant imitation, and early marketing for mined diamonds leaned hard on the idea that only mined stones were genuine. Price adds to the suspicion: when a 4 carat lab-grown ring costs less than half of a similar natural ring, people assume something must be missing. What is missing is rarity and resale value, not diamond. That is a real trade-off and worth thinking about, but it is a question of value, not authenticity.

1. Is it lab-grown or natural? The answer must be clear and in writing.
2. Is there a grading report? If yes, which lab and what number, so you can check it online.
3. What are the 4Cs? Color, clarity, carat and, for rounds, cut grade.
4. Is there an inscription? A loupe should show it on the girdle if the stone was graded.
5. Is the metal stated? Karat and color, such as 14K white gold.

Every lab piece in our catalog carries "Lab Diamond" in its name, and the house rings are graded E color and VS1 clarity in our inventory.

If a seller cannot answer the first question plainly, walk away. Vague names like "lab stone," "created gem" or "VVS iced" with no mention of diamond often hide moissanite or cubic zirconia. A lab-grown diamond seller has no reason to be vague, because the stone is exactly what it says: real diamond, grown in a lab.

Here is what real lab-grown diamond jewelry looks like with full information on the tag:

Compare origins directly in lab vs natural diamonds, browse lab diamond engagement rings or the pear lab diamond rings, or see everything in diamond jewelry.