Why we set only lab-grown diamonds

When I founded Maré, I wanted to be able to tell every customer exactly where their stone came from. With mined diamonds, even good ones, the honest answer is often a long chain of traders. With lab-grown diamonds, the answer is a single grower, a single date and a certificate number. That was the beginning of the decision.

What a lab-grown diamond is

A lab-grown diamond is a real diamond. It is pure carbon arranged in the same cubic crystal structure as a mined stone, with the same hardness of 10, the same refractive index and the same fire. It is not a simulant like cubic zirconia or moissanite. Without specialist equipment, no jeweller can tell the difference.

Stones are grown in one of two ways. In CVD (chemical vapour deposition), a thin diamond seed is placed in a chamber of carbon-rich gas, and carbon atoms settle onto it layer by layer. In HPHT (high pressure, high temperature), the conditions deep in the earth are recreated in a press. Either way, a rough crystal grows in a few weeks rather than a few billion years, and is then cut and polished exactly like a mined stone.

How we choose them

• Every centre stone is independently graded for cut, colour, clarity and carat, the same four Cs used for mined diamonds.
• Aure's 0.50 ct centre stone is VS1 clarity and F colour: eye-clean and bright white.
• Larger stones carry a microscopic laser inscription on the girdle that matches their certificate.
• We ask every grower about their energy source and favour those running on renewable power.

Because the stone costs less, we can spend more on the cut. And the cut is what you actually see.

What about value?

Lab-grown diamonds cost considerably less than mined stones of the same grade, and they do not carry the same resale market. We are open about that. We see a diamond as something to wear, not something to trade, and we would rather you spent your budget on a better cut, a well-made setting and gold that was not mined for it.