Lab-Grown vs. Natural Diamonds: A Complete Comparison Guide

Two round diamonds side by side on a pale stone surface, one cooler and one warmer in tone

Lab-grown diamonds have gone from a niche option to roughly half of all engagement ring sales in just a few years. If you’re shopping for an engagement ring, you’ll almost certainly have to choose between a lab-grown and a natural (mined) diamond. This guide explains exactly how they differ — and how they don’t.

Are lab-grown diamonds real diamonds?

Yes. A lab-grown diamond is chemically, physically and optically identical to a natural diamond. It is pure crystallized carbon with the same hardness (10 on the Mohs scale), the same brilliance and the same fire. The only difference is origin: one crystallizes in the earth over billions of years, the other in a laboratory over a few weeks using one of two methods — HPHT (high pressure, high temperature) or CVD (chemical vapor deposition).

This is different from a diamond simulant like cubic zirconia or moissanite, which only look like diamond but have different physical properties.

Price: the biggest difference

A lab-grown diamond typically costs 60–85% less than a natural diamond of the same 4C grades. In practice this means you can choose a significantly larger or higher-quality stone for the same budget — for example, a 2-carat lab-grown diamond for roughly the price of a 1-carat natural one.

Resale and long-term value

Natural diamonds hold a modest secondhand value because supply is finite. Lab-grown diamond prices have been falling as production scales up, so their resale value is currently low. If you view a ring as an heirloom to keep rather than an investment to sell, this may not matter to you — but it’s an honest trade-off to understand.

Sourcing and environmental impact

Both options can be responsible choices:

  • Lab-grown: No mining. Impact depends on the energy source used to power the growing reactors.
  • Natural: Look for diamonds sourced under the Kimberley Process and from suppliers with traceable, conflict-free supply chains.

Do they look different?

No. Once set in a ring, a lab-grown and a natural diamond of the same 4C grades are indistinguishable to the naked eye — and even to a jeweler without specialized equipment. Both are graded on the same 4Cs of cut, color, clarity and carat.

How to tell them apart

Only specialized laboratory instruments can distinguish them. Lab-grown diamonds are also laser-inscribed on the girdle with a note of their origin and a certificate number from a lab such as IGI or GIA.

Quick comparison

Lab-Grown Natural
Chemical composition Pure carbon Pure carbon
Hardness (Mohs) 10 10
Sparkle Identical Identical
Price 60–85% less Higher
Resale value Low Modest
Rarity Made to order Finite supply
Certificate GIA / IGI GIA / IGI

Which should you choose?

  • Choose lab-grown if you want the largest or highest-quality diamond for your budget and aren’t concerned about resale.
  • Choose natural if the rarity, geological origin and long-term value of a mined diamond matter to you.

There is no wrong answer — both are genuine diamonds that will last for generations.

Frequently asked questions

Are lab-grown diamonds fake?

No. They are real diamonds with the same chemical and physical properties as mined diamonds. Only simulants like cubic zirconia and moissanite are not diamonds.

Do lab-grown diamonds pass a diamond tester?

Yes. Because they are true diamond, they test as diamond on a standard thermal or electrical tester.

Will a lab-grown diamond get cloudy over time?

No. A diamond — lab-grown or natural — will not cloud, fade or lose its sparkle. Routine cleaning keeps it brilliant.

See both options in person

Our NYC studio offers both lab-grown and natural diamonds in every setting. Browse our engagement ring collection or contact us to compare stones side by side.