Lab grown diamonds cost less mainly because their supply chain is shorter and more efficient. A mined diamond passes through exploration, extraction, and several trading and cutting stages before it reaches a retailer, and its price carries the cost and the scarcity built into that long chain. A lab grown diamond is produced directly, in weeks, with a known cost, and supply can scale to meet demand, which removes the scarcity premium. As production capacity has grown, lab grown prices have fallen further, so the same size and quality of stone now costs significantly less than its mined equivalent, often less than half. The diamond itself is not lower quality. You are paying for the stone, not for a long mining and trading chain or for engineered scarcity. For buyers, that is the central appeal: the same diamond, for far less.
See the difference in our engagement ring collection, where each ring is priced direct from our Hatton Garden studio. A larger stone in a simple setting like the Amaris shows the saving best, and you can compare shapes in our oval engagement rings.
The mined diamond supply chain
A mined diamond passes through exploration, extraction, sorting, polishing, wholesale and retail before it reaches a buyer. Each step adds a margin. The retail price also carries an element of scarcity, which has historically been managed to support prices.
The lab grown supply chain
A lab grown diamond is produced in a facility, cut and polished, certified and sold. There is no exploration, no extraction, no scarcity premium. Supply can scale up or down with demand, which keeps prices grounded in production cost rather than in market positioning.
What you actually get for the saving
The same diamond, on every measurable property: hardness, brilliance, certification, durability. The saving means you can choose a larger or higher quality stone for the same budget, or spend less for the size you want. Either way, you are not trading down on the stone itself.
What that looks like in real prices
At Luma a 1ct IGI certified lab grown diamond in a plain 18k white gold solitaire is around £1,350 to £1,400. The 2ct version of the same ring is around £1,500 to £1,550. Going up a full carat adds roughly £150.
That one figure explains the article better than any description of a supply chain. In mined diamonds, price rises steeply with size because large rough is rare and that rarity is priced in. Lab grown production does not work that way, so the cost of a larger stone tracks the cost of growing it rather than the odds of finding it. Prices shift with the individual diamond, so treat these as typical rather than fixed.
Related questions
Will lab grown diamond prices keep falling?
They may continue to fall as production scales, which is good news for buyers. The diamond itself does not change, only the price you pay for it.
Are mined diamonds worth the extra?
Only if you specifically value the geological origin of a stone formed naturally in the earth. On every other measure, including beauty, hardness and certification, a lab grown diamond is identical.
Does the cheaper price mean lower quality?
No. The price difference is supply chain, not material. The diamond itself is the same.
How much cheaper is a lab grown diamond in practice?
At Luma a 1ct IGI certified stone in a plain 18k white gold solitaire is around £1,350 to £1,400, and our lowest priced complete engagement ring starts from around £820. A mined equivalent of the 1ct ring would typically sit at two to three times that. The clearest illustration is size: doubling the centre stone from 1ct to 2ct costs us about £150 more, where a mined 2ct sits far above a mined 1ct.