☕ JCK Wraps With Natural Diamond Fever, Lab Diamonds Fuel AI Chips, and Signet Grabs The Clear Cut. Wednesday, June 4

The JCK Las Vegas 2026 show just closed its doors, and the verdict is in: natural diamonds are having a serious moment. While the trade floor went quiet, the industry kept moving.

The jewelry industry's biggest annual gathering wrapped on June 1 at the Venetian Expo in Las Vegas, and the vibe was unmistakably bullish on natural stones. Retailers reported strong demand for fancy shapes, with ovals, pears, and marquise cuts stealing the spotlight from rounds (which still account for about 62% of sales, but that gap is narrowing). Yellow gold continued its multi-year resurgence, and men's jewelry was flagged as a legitimate growth category. The standout moment: Botswana debuted a 63-carat traceable diamond, leaning hard into the provenance-and-luxury story that natural diamond advocates have been building for years.

If you skipped JCK this year, here's your homework: look at your fancy shape inventory. Ovals in particular are being called the new "classic" by show-floor buyers, and their visual size advantage (they face up larger than rounds of the same carat weight) is a genuine sales conversation starter. Yellow gold is not going away. If you're still defaulting to white gold settings as your showcase default, that's worth revisiting.

The broader picture is this: the industry is consciously bifurcating. Natural diamonds are being repositioned as rare, provenance-driven luxury items for people who want meaning and heritage with their purchase. Lab-grown is being sold on value, sustainability, and size. The retailers who will thrive are the ones who can articulate both value propositions clearly and confidently, rather than treating the two categories as competitors fighting for the same customer.

This one reads like a science fiction headline, but it's real. Bloomberg reported on June 2 that Chinese lab-grown diamond producers are now supplying diamond heat spreaders to AI chip manufacturers. Diamond's thermal conductivity is five times that of copper, and Nvidia's next-generation GPUs are adopting a "diamond composite plus liquid cooling" thermal solution to handle the heat generated by increasingly dense AI chips. SF Diamond and Henan Liliang Diamond have already begun commercial shipments, and Chinese lab-grown diamond stocks have surged over 90% year-to-date, with some individual producers up 40-51% in a single week.

Two practical takeaways for your store. First, industrial demand for lab-grown diamond material could put a floor under lab diamond prices, which have been falling for years. They're already up about 3% in recent months. If customers ask "will lab diamonds keep getting cheaper?", the honest answer is no longer obviously yes. Second: this is a genuinely fascinating conversation starter. Telling a customer that the same basic material in their ring is now cooling the AI chips powering ChatGPT? That's a story people repeat at dinner parties.

On May 28, Signet Jewelers announced it's buying The Clear Cut, a New York-based online jeweler known for its natural diamond advocacy and its loyal Gen Z following. The acquisition price wasn't disclosed, but Signet CFO Joan Hilson called it a "tuck-in investment focused on enhancing Signet's capabilities in high-end natural diamond sales." The Clear Cut will be folded into Blue Nile, which Signet is repositioning as a higher-end, natural diamond-focused brand. The Clear Cut's own website will eventually be discontinued.

Here's what this means in plain terms: your biggest online competitor in the natural diamond bridal space is getting sharper, better-funded, and more sophisticated. The Clear Cut's audience is 75% under 35 and 88% female. Those are exactly the customers you want walking through your door for an engagement ring. The way to win against a better-resourced Blue Nile isn't to out-discount them. It's to out-experience them. Signet can't replicate the relationship you build with a couple over three visits and a custom setting.

De Beers cut its 2026 production guidance to 21-26 million carats, down from 26-29 million. At the same time, rough diamond prices have been cut 10-15%, with the consolidated average realized price declining 19% year-over-year to $101 per carat in Q1 2026. The miner is throttling supply while reducing prices to move inventory, a dual signal that reflects just how much lab-grown competition has disrupted the rough market.

The practical upshot: the cost of rough natural diamonds is lower right now than it has been in years. If you're buying diamond inventory, your suppliers' input costs have dropped. Lower rough prices don't automatically flow through to lower wholesale prices for you, but knowing the market context gives you something to talk about with your vendors. It's a fair conversation to have.

The US-India interim trade framework finalized earlier this year brings genuine relief to the diamond supply chain. Under the deal, the tariff on loose natural diamonds and colored gemstones imported from India drops to 0%. Finished diamond jewelry gets an 18% tariff, down from 25% (and well below the punishing 50% duties that were briefly in place). India's gem and jewelry exports to the US had fallen from $3.64 billion to $1.45 billion year-over-year under the old tariff regime. This is a structural fix for a supply chain that was under real pressure.

India cuts and polishes the vast majority of the world's diamonds. When Indian processing gets hit by tariffs, that pain flows through to every retailer who buys diamonds. The 0% tariff on loose stones is the most important number here. If your vendors haven't passed those savings along yet, ask. The deal has been in place long enough that the supply chain has had time to adjust.

JCK is wrapped, the Las Vegas hotels are clearing out, and the real work begins: taking what happened this week and turning it into actual decisions. Fancy shapes, AI diamonds, a sharper Blue Nile competitor, lower rough prices, and a repaired India supply chain. There's a lot to work with this week. Go make some sales.

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— Karat Clark, Carats & Coffee