Updated 2 November 2026
A lab grown diamond is carbon grown into a diamond crystal inside a machine, by one of two methods: CVD, where a carbon rich gas builds the crystal on a thin diamond seed, or HPHT, where heat and pressure crystallise a carbon source around a seed. It is then cut, polished, graded and inscribed like any diamond.
How is a lab grown diamond made, step by step?
- The seed. Growth starts from a thin slice or a tiny piece of diamond, called the seed.
- The growth. The seed goes into a CVD chamber or an HPHT press, and carbon atoms build onto it. This takes weeks to months, depending on the size and quality wanted.
- The rough stone. What comes out is a rough diamond crystal, which looks nothing like a finished stone yet.
- Cutting and polishing. The rough is cut and polished into its shape, as any diamond is.
- Grading. An independent laboratory such as IGI grades the stone on the 4Cs. The report says the diamond is lab grown and notes how it was made.
- Inscription. The report number is laser inscribed on the girdle, the stone's outer edge, so the paper and the diamond can be matched.
What is the difference between CVD and HPHT?
| CVD | HPHT | |
|---|---|---|
| Stands for | Chemical Vapour Deposition | High Pressure High Temperature |
| How it grows | Carbon rich gases, typically methane and hydrogen, are activated in a vacuum chamber, and carbon settles on the seed layer by layer | A seed sits with a carbon source such as graphite in a press; the carbon dissolves in a metal catalyst and recrystallises on the seed |
| Temperature | 700 to 1,300°C | 1,300 to 1,600°C |
| Pressure | Low | 5 to 6 GPa, about 50,000 to 60,000 atmospheres |
Neither method makes a better diamond on its own. The grading on the report decides that. Our CVD vs HPHT guide goes deeper, and our CVD diamond price guide covers what they cost.
Is the result the same as a diamond formed in the earth?
In material, yes. Both are carbon in the diamond crystal structure, with the same hardness of 10 on the Mohs scale, the same refractive index of 2.417 and the same density. The difference is origin, and it shows only in trace growth patterns that laboratory instruments can read. No one can tell by eye. See can a jeweller tell a lab grown diamond, and for what growing a diamond changes, the evidence on ethics.
How does Nivara choose its lab grown diamonds?
Nivara sources primarily CVD diamonds, and will source an HPHT stone if it meets a customer's brief and the IGI specification.
What comes with every piece
- Solitaires in VVS or IF clarity, D or E colour and ideal cut, with hearts and arrows in every round. Smaller diamonds in VVS or VS clarity, E or F colour.
- IGI certification, and on solitaires the report number laser inscribed on the stone, so the paper and the diamond are one.
- 14k or 18k BIS hallmarked gold.
- A lifetime exchange at 100% of the current gold and diamond value, and a lifetime buyback at 100% gold and 85% diamond value.
- Lifetime polishing, cleaning and prong tightening, for as long as the piece is worn.
To see the finished pieces, browse our lab grown diamond jewellery, all made in 14K or 18K gold with IGI certified diamonds.
Explore Nivara's lab grown diamond engagement rings and men's diamond rings, all IGI certified and available for a private viewing at our Hyderabad, Bangalore, Indore, and Ahmedabad showrooms.
Frequently asked questions
What is a lab grown diamond made of?
Carbon, arranged in the diamond crystal structure. It starts from a small diamond seed, and carbon atoms build onto that seed until it becomes a rough diamond crystal.
How long does it take to grow a lab grown diamond?
Weeks to months, depending on the carat size and the quality wanted. Cutting, polishing and grading come after that.
Is a lab grown diamond chemically the same as a diamond formed in the earth?
Yes. Both are carbon in the diamond crystal structure, with the same Mohs hardness of 10, the same refractive index of 2.417 and the same density. Only the origin differs.
Which method does Nivara use?
Nivara sources primarily CVD diamonds, and will source an HPHT stone if it meets a customer's brief and the IGI specification.
How does a laboratory tell a lab grown diamond apart?
With spectroscopy and deep ultraviolet fluorescence imaging, which read trace elements and the pattern in which the crystal grew. CVD diamonds grow in flat layers, HPHT diamonds in sectors around a seed, and earth formed diamonds in octahedral layers. The pattern is permanent, so origin can always be determined.
