For most of the 2010s De Beers was the loudest voice against lab-grown diamonds in jewellery. In May 2018 it became a seller of them. Seven years later it stopped. The reversal is one of the most discussed episodes in the category and also one of the most misremembered, so here is the sequence with a source for each step.
The opposition, 2015–2017
De Beers was a founding member of the Diamond Producers Association, formed in 2015 by the seven largest miners, whose "Real is Rare" campaign launched in 2016 to sell natural diamonds to millennials 1. Fortune's report on the day of the Lightbox announcement summarised the position plainly: for years De Beers had "vowed that it wouldn't sell stones made in laboratories" 2. JCK noted that its executives had "routinely disparaged lab-grown diamonds as 'less precious' than naturals" 4.
This was not because De Beers lacked the technology. Its subsidiary Element Six had grown synthetic diamond for industrial uses for decades and supplied the detection equipment the trade used to screen out undisclosed synthetics 2.
The announcement, 29 May 2018
De Beers Group announced Lightbox Jewelry on 29 May 2018: a fashion brand selling pink, blue and white lab-grown diamonds in earrings and pendants, US$200 for a quarter carat and US$800 for a carat, on sale in September, backed by a US$94 million Element Six plant near Portland, Oregon, capable of 500,000 rough carats a year. Stones of 0.2 carats and above would carry an invisible Lightbox logo 3. Chief executive Bruce Cleaver described the target as "affordable fashion jewelry that may not be forever, but is perfect for right now" 3.
Why: the stated reasons
De Beers gave two explanations at launch, and a third became clear later.
Consumer research. Sally Morrison, Lightbox's marketing head, told JCK that focus groups "wanted [lab-grown diamonds] to be for less serious occasions, more fashion, more fun" 4. Lightbox was built to serve that demand, not the engagement market.
Pricing the category down. Lightbox's flat US$800 per carat was reported as about 75% below existing lab-grown competitors. JCK recorded the logic: executives believed "synthetics should not be priced as inherently rare or precious things" 4. By selling lab-grown cheaply and calling it fashion, De Beers could draw a line between it and natural diamonds in the consumer's mind. David Prager's answer to the accusation of cynicism was that "you don't invest $94 million in a project if you are not enthusiastic about it" 4.
Defending the natural business. Whatever the motives in 2018, by 2024 De Beers was explicit that lab-grown had cannibalised natural sales and that the point of its strategy was to separate the two categories 8.
What Lightbox did, 2018–2024
Lightbox went on sale in September 2018, online in the US, and reached Bloomingdale's and Reeds Jewelers in October 2019 5. It later tried engagement rings; that trial ended in September 2023, with De Beers citing the volumes needed to make it pay 6. On 10 May 2024 Lightbox cut prices by up to 40%: colourless DEF stones from US$1,500 to US$900 a carat, GH from US$800 to US$600, IJ from US$800 to US$500, "to more closely align with current jewelry industry dynamics" 7. Weeks later, as Anglo American prepared to spin De Beers off, chief executive Al Cook announced the Origins strategy: double retail, build "the world's greatest jewelry maison", and exit lab-grown jewellery altogether 8.
The closure, 8 May 2025
De Beers announced its intention to close Lightbox on 8 May 2025. The release noted that Lightbox had launched at US$800 per carat and that wholesale lab-grown prices had since fallen around 90%, "tracking closer to a cost-plus model". Cook said the closure "reflects our commitment to natural diamonds" and that the decline of lab-grown "underscores the growing differentiation between these factory-made products and natural diamonds". Element Six would focus on industrial synthetic diamond for semiconductors and quantum technology, and Lightbox warranties would be honoured 9 10.
The sequence
| Date | Event | Source |
|---|---|---|
| 2015–16 | DPA formed; "Real is Rare" launches; De Beers says it will not sell synthetics | 1 2 |
| 29 May 2018 | Lightbox announced, US$800/ct, September launch | 3 |
| Sept 2018 | Lightbox on sale | 5 |
| Oct 2019 | Bloomingdale's and Reeds stock Lightbox | 5 |
| Sept 2023 | Lightbox engagement-ring trial ends | 6 |
| 10 May 2024 | Prices cut up to 40% | 7 |
| May–June 2024 | Origins strategy: exit lab-grown jewellery | 8 |
| 8 May 2025 | Closure announced; wholesale prices down ~90% | 9 |
How to read it
Two readings are common and both have evidence. One is that De Beers entered lab-grown to control it: by pricing the category as disposable fashion it protected the natural-diamond premium, and when the market fell to where it had said it belonged, it left. The other is that it entered in good faith, spent US$94 million, and was overtaken by Indian and Chinese producers who took prices far below anything Lightbox had planned for. The company's own statements support the first reading at launch and the second at closure. What is not in dispute is the timing: the announcement came one month after Courbet and Lark & Berry had launched in May 2018, and the product reached consumers four months after that. See 2018 for the month-by-month record and the price collapse for what happened to the market Lightbox left.