Lab-Grown Diamonds Guide: How They're Made, Graded and Bought

Yes. They are crystallised carbon with the same structure, hardness and optical properties as mined diamonds. Only their origin differs, which is why they must be clearly described as lab-grown.

Not with the naked eye or a standard jeweller's loupe. Laboratories use spectroscopy and specialised imaging to identify origin, and reputable reports state it clearly.

Yes. Standard thermal and electrical testers respond to lab-grown diamonds just as they do to natural ones, so a tester alone can't tell you a diamond's origin.

Resale value for lab-grown diamonds is generally limited and less predictable than for natural diamonds, partly because production costs have fallen. It's sensible to buy for enjoyment rather than as an investment and to ask about buy-back or upgrade policies.

HPHT recreates the high pressure and heat of the earth's mantle, while CVD builds diamond layer by layer from a carbon-rich gas. Both produce real diamonds, and each can leave typical traits that a grading report or gemmologist can explain.

Under Australian Consumer Law, sellers must not mislead buyers about a diamond's origin. In practice, a lab-grown diamond should be clearly described with a qualifier such as 'lab-grown' or 'laboratory-created'.