Yes. Lab-grown diamonds are real diamonds - chemically, physically, and optically identical to natural diamonds. They are not cubic zirconia, moissanite, or diamond simulants. They are diamonds, grown in a laboratory rather than extracted from the ground, certified by the same grading institutions using the same 4Cs standards. The only verified difference between a lab-grown diamond and a mined diamond is origin and price.
This is not a marketing claim. It is the scientific and gemological consensus as of 2026.
What Makes a Diamond a Diamond?
A diamond is defined by its chemical composition: pure crystallised carbon arranged in a cubic crystal structure. This structure - formed under extreme heat and pressure - gives diamonds their defining properties:
- Hardness: 10 on the Mohs scale - the hardest naturally occurring substance
- Refractive index: 2.417 - the property that creates brilliance and fire
- Thermal conductivity: the highest of any natural material
- Chemical composition: 100% carbon
Lab-grown diamonds share every one of these properties. When a gemologist measures a lab-grown diamond against a natural diamond using spectrometry, the atomic structure is identical. The carbon bonds are identical. The crystal lattice is identical.
The Federal Trade Commission (FTC) confirmed this in 2018, updating its definition of "diamond" to remove the word "natural" - acknowledging that a diamond does not need to come from the earth to be a diamond.
How Are Lab-Grown Diamonds Made?
Two methods are used commercially to grow diamonds in a laboratory. Both replicate the conditions under which natural diamonds form.
HPHT - High Pressure High Temperature: A diamond seed crystal is placed in a press alongside carbon source material. The press applies temperatures of approximately 1,300–1,600°C and pressures of 5–6 GPa - mimicking the conditions 150–200km beneath the earth's surface. Carbon crystallises around the seed, forming a diamond over 2–4 weeks.
CVD - Chemical Vapour Deposition: A diamond seed is placed in a chamber filled with carbon-rich gas (typically methane). Microwave energy ionises the gas into plasma, causing carbon atoms to layer onto the seed and crystallise into a diamond. CVD diamonds grow over 4–6 weeks.
Both methods produce diamonds with the same chemical composition as mined diamonds. Neither produces a "lesser" diamond - quality is determined by the 4Cs grading, not the growth method. Every IGI-certified lab-grown diamond from Dileti includes the growth method on the certificate.
Can a Gemologist Tell the Difference Between Lab-Grown and Natural?
Not with the naked eye or standard gemological equipment. Professional gemologists cannot distinguish a lab-grown diamond from a natural diamond through visual inspection, loupe examination, or standard refractive index testing.
Specialised equipment - specifically devices that measure UV fluorescence patterns or detect trace element signatures - can identify growth origin. Laboratories including IGI and GIA have developed detection instruments specifically because the stones are otherwise indistinguishable.
Lab-Grown vs Natural Diamonds: Direct Comparison
| Property | Lab-Grown Diamond | Natural Diamond |
|---|---|---|
| Chemical composition | 100% carbon | 100% carbon |
| Crystal structure | Cubic | Cubic |
| Hardness (Mohs) | 10 | 10 |
| Refractive index | 2.417 | 2.417 |
| IGI / GIA certifiable | Yes | Yes |
| Visually distinguishable | No | No |
| 4Cs grading applicable | Yes | Yes |
| Price vs natural equivalent | 60–70% lower | Baseline |
| Environmental origin | Laboratory | Mined |
What Do Lab-Grown Diamonds Look Like?
Identical to natural diamonds. The same cuts - round brilliant, oval, emerald, cushion, pear - are applied to lab-grown diamonds using the same equipment and by the same cutters who work with natural stones. An Excellent-cut lab-grown round brilliant produces the same 58-facet light return pattern as an Excellent-cut natural round brilliant.
Are Lab-Grown Diamonds Worth Buying?
For a buyer who prioritises cut quality, visual appearance, and budget efficiency: yes. For a buyer who prioritises long-term resale value as an investment: natural diamonds have a marginally better resale track record, though both depreciate from retail price. Diamonds - natural or lab-grown - are jewellery, not investment assets.
What to Look For When Buying a Lab-Grown Diamond
Regardless of growth method, the quality of a lab-grown diamond is determined by the same 4Cs:
- Cut: Excellent or Very Good - never compromise on cut.
- Colour: G–I - appears white in all 18K gold settings.
- Clarity: VS2–SI1 - eye-clean at most carat weights.
- Carat: choose last, once cut, colour, and clarity are confirmed.
Frequently Asked Questions
Q1. Are lab-grown diamonds the same as cubic zirconia?
No. Cubic zirconia is a diamond simulant with completely different chemical composition, hardness, and optical properties. Lab-grown diamonds are chemically identical to natural diamonds.
Q2. Do lab-grown diamonds pass a diamond tester?
Yes. Lab-grown diamonds have the same thermal conductivity as natural diamonds and pass all standard tests.
Q3. Are lab-grown diamonds graded by IGI the same as natural diamonds?
Yes. IGI grades lab-grown and natural diamonds using identical 4Cs methodology.
Q4. Why are lab-grown diamonds cheaper?
Supply. Lab-grown diamonds can be produced in 2–6 weeks in a controlled environment, whereas natural diamonds take billions of years to form and require costly mining.
Q5. Do lab-grown diamonds last as long as natural diamonds?
Yes. With a hardness of 10 on the Mohs scale, they are as scratch-resistant and durable as natural diamonds.
