Lab Diamond Guide

The science

How a lab diamond is grown

A diamond is a diamond, whether it is grown in a laboratory or taken from the ground.

Our stones begin as a slender diamond seed placed inside a chamber that recreates the conditions found deep within the earth. Carbon crystallises around the seed atom by atom, over several weeks, until a rough diamond emerges — chemically, optically and physically identical to a mined stone.

Because growth is controlled rather than accidental, our gemmologists can select stones of exceptional purity: the clarity, colour and precision we require are achieved far more consistently than nature allows.

Shape guide

The ten cuts

Round brilliant

Classic and timeless: fifty-seven facets engineered to return the greatest possible light.

Oval

The brilliance of a round cut in an elongated silhouette that flatters the hand.

Radiant

Trimmed corners and brilliant faceting: the elegance of an emerald with the fire of a round.

Emerald

Long step facets create a hall-of-mirrors effect and reward exceptional clarity.

Pear

A teardrop between round and marquise — singular, graceful, quietly theatrical.

Cushion

Softly rounded corners and vintage charm, with generous depth of sparkle.

Princess

Sharp corners and brilliant facets for a modern, architectural line.

Asscher

A square step cut with cropped corners and a deliberate, vintage geometry.

Marquise

Pointed ends maximise apparent size and lengthen the finger.

Heart

The most personal silhouette, demanding perfect symmetry from the cutter.

Quality

Reading the four C's

Carat

Weight, not size. Two stones of equal carat can read very differently depending on cut and proportion.

Colour

We work in the colourless range, D to F, so the stone reads as pure white light.

Clarity

Astrea selects VVS1 and VVS2 stones: inclusions are invisible to the eye and difficult to find under a loupe.

Cut

The one C decided by human hand — and the one that determines whether a diamond truly comes alive.

Value

A Diamond Is a Diamond

A diamond is a diamond — whether it is created above ground or formed beneath it. This is not a matter of opinion, but of science.

Lab-grown and mined diamonds share the same fundamental chemical composition and crystal structure, and the same optical properties, brilliance, hardness and durability. Their distinction lies in their origin — not in their identity as diamonds.

So why can the difference in price be so extraordinary?

A mined diamond carries with it the considerable economics of extraction: exploration, mining infrastructure, heavy machinery, labour, energy, transportation and the complex journey from deep within the earth to the jewellery house.

A lab-grown diamond is created using highly advanced technology in a precisely controlled environment, removing much of the enormous cost associated with finding and extracting diamonds from the earth.

The result is remarkable: the same diamond material, without the economics of mining.

Today, an exceptional two-carat lab-grown diamond — D colour, VS2 clarity or above, with exceptional light performance — can be acquired for approximately $8,000, while a mined diamond of equivalent quality may command $60,000 or more.

And this is where the conversation about value becomes particularly important.

A diamond is a jewel, not a financial investment. It is something extraordinary to own, to wear, to celebrate and, perhaps, one day, to pass on. Its emotional value may be immeasurable, but its retail purchase price should not be confused with its resale value.

A mined diamond purchased for $60,000 may lose $30,000 or more of its retail purchase price upon resale. Even in the purely theoretical scenario in which both diamonds ultimately had no resale value at all, the financial exposure is fundamentally different: with one, you began at $8,000; with the other, at $60,000.

In reality, diamonds do have a secondary market. The point is not that a lab-grown diamond has no value. It is that when you pay dramatically less at the outset for an equivalent diamond, there is dramatically less value at risk.

At Astrea London, we believe this represents a new expression of luxury: one defined not by the cost of extraction, but by the excellence of the diamond itself.

The same beauty. The same brilliance. The same permanence. A diamond is a diamond — with a more intelligent approach to value.

— Nathalie Morrison, Founder, Astrea London

Certification

Independently verified

Every centre stone is graded by IGI and accompanied by its own report, which you may verify directly with the laboratory. Precious metals are hallmarked to UK standards and Astrea London is a registered Assay Assured Jewellery Retailer.