The honest framing first
This site is published by Lark & Berry, a London designer house that has worked exclusively with lab-grown diamonds since 2018. We sell bespoke engagement rings. That is a direct commercial interest in the answer to this question, so the fairest thing we can do is set out plainly where an online retailer beats us, and where we think a designer house earns its price. If you finish this page and decide an e-tailer is right for you, that is a perfectly good outcome.
Where the online retailer wins
Price on the stone. Wholesale lab-grown prices fell 26% in 2025 and have dropped roughly 96% since 2018.2 Online retailers operating at volume pass most of that through. For a 1 carat round, UK retail listings in 2026 run from about £1,050 at the low end,5 and a large e-tailer will usually sit near the bottom of that band. A designer house rarely will.
Choice. An e-tailer can show you several thousand loose stones with certificates, video and filters. No workshop holds that inventory. If you want to compare forty 1.5 carat ovals side by side for bow-tie and length-to-width ratio, the online model is simply built for it.
Speed and convenience. Stock settings ship in days. A bespoke ring takes four to eight weeks because it is made once, for you.
Standard solitaires. If the brief is "a round or oval stone, a plain band, claws" then the design is largely solved. A well-made stock solitaire from a reputable online retailer is a good ring, and paying designer prices for it buys you little that you can see.
Where a designer house wins
Design that is not in the catalogue. Most of what a designer house does is not available as a stock item: a bezel shaped to a particular stone's outline, a band that tapers asymmetrically, a cluster of matched fancy shapes, a setting that pairs with an existing heirloom. That is the part of the brief an e-tailer cannot filter for.
Setting quality. Online stock settings are cast in volume and set on a production bench, often with the stone secured after the metal has already been finished. A designer house sets by hand, cuts the seats to the individual stone, and finishes after setting. The difference shows in claw symmetry, how flush a bezel sits and how the ring wears over years rather than months.
Matched stones. For an eternity band, a pair of earrings or a five-stone ring, the stones need to match in colour, cut proportions and size to within fractions of a millimetre. Lab-grown production makes this far easier than mined supply, as explained on the matching page, but someone still has to do the matching. A designer house does; an e-tailer sells you what is in stock.
One accountable maker. When an online retailer's setting fails, you deal with a returns department; the stone came from one supplier, the mount from another and the setter from a third. A designer house made the whole ring and is answerable for the whole ring. That matters more than it sounds when a claw lifts in year six.
Stone selection that is not grade-driven. Since GIA moved lab-grown stones to a two-tier "Premium" or "Standard" assessment in October 2025,3 and with most lab-grown certificates coming from IGI, the paper alone tells you less than it used to. A house that handles stones daily will reject a "D VVS" with a grey undertone or a dull cut that passes on paper. Online, you are doing that job yourself from a video.
What the market is telling you
Lab-grown is now the default for engagement rings, not the alternative. The Knot Worldwide's 2026 study found 61% of US engagement rings bought in 2025 had a lab-grown centre stone.1 UK retailer data points the same way. Meanwhile De Beers closed Lightbox, its own lab-grown fashion brand, in 2025.4 The consequence for buyers is that the stone has become a commodity and the design and making is what now distinguishes one ring from another. That is the structural reason designer houses still exist in a category where the raw material has collapsed in price.
A practical way to decide
Ask three questions:
- Is the design standard? If yes, an e-tailer is likely the better buy.
- Does the piece need matched stones, a fancy shape, or a setting that does not exist as stock? If yes, a designer house.
- Who do you want to be answerable in ten years? If you want one name, a designer house.
For what the commissioning process involves, timelines, deposits and what a budget buys in a bespoke context, our sister site covers that in detail at commissionedjewellery.com.6 This page is deliberately about the stone and the maker, not the process.
What this page does not say
It does not say designer houses sell better diamonds. It does not name or rank online retailers. And it does not pretend Lark & Berry is a neutral party: we are one of the designer houses described above, and you should read the argument with that in mind.