Diamond Market, Week 17, 2026

Listing activity fell off a cliff in week 17. New listings dropped 38% to just over 1.08 million, the lowest weekly intake across the seven weeks I've tracked this cycle. Off-market removals fell even harder, down 58% to 783,000. Yet active inventory barely moved, sitting at 26.76 million stones, essentially flat on the prior week. The market didn't shrink or grow; it just went quiet. Total inventory value, though, slid 10% to $98.9 billion, a notable pullback from last week's $110 billion. That gap can't be explained by count alone. The mix shifted.

Prices softened across both origins. Lab-grown median prices on new listings came in at $820, down 23% from the prior week's $1,060, while natural medians dropped to $1,344, off about 20%. Per carat, lab-grown stones landed at $490 (down 32%), and naturals at $2,326 (a more modest 3.5% dip). The overall median price edged down 1.6% to $1,103, keeping the trend over seven weeks essentially flat. Lab-grown share held steady at 65.3%, barely changed from 65.6% the week before. The drift upward over the broader window (from 62.4% in week 11) has plateaued for now.

Shape pricing showed some dramatic swings, though context matters. Asscher medians cratered 59% to $1,131 on nearly 8,900 new listings, a real move with enough volume behind it to be meaningful. Ovals dropped 49% to $1,084 across more than 160,000 new stones. Radiants fell 37% to $1,270. On the other side, trillions doubled in median price to $2,046, but only 260 stones listed. That's noise, not signal. Rounds continued to dominate volume at 49% of all new listings (532,000 stones), with a median of $795.

The spread story is quietly worth watching. Median cross-retailer spread hit 87.5%, a new low for the seven weeks I track, down from 88.3% last week and well off the 92.7% peak in week 13. At the same time, cross-retailer overlap ticked up to 48.3%, its highest reading in this window. More stones are appearing at multiple retailers, and the price gap between cheapest and most expensive listing for the same stone is narrowing. For buyers, that's a solid combination: more competition, tighter pricing.

At the top end, the most expensive stone listed this week was a 20.28ct E VVS1 natural round at $2.77 million. The largest was a 53.68ct lab-grown cushion, H VS1, listed at two different price points ($88,000 and $137,000) across different retailers. That $49,000 gap on the same stone is a useful reminder of why comparison shopping matters, even at scale. Concentration remained moderate, with the top five retailers accounting for 51% of new listings.

The quiet week raises a question worth tracking: is this a seasonal lull, or are retailers pulling back on listing velocity as prices soften? If new listings stay near this floor while removals stay subdued, inventory will drift sideways and pricing pressure should ease. But if the softness in lab-grown per carat pricing (now at $490, down from $725 just a week ago) reflects something more structural, the next few weeks will tell us whether buyers step in to absorb the value or sit on their hands waiting for further drops.

Diamond Market Charts, Week 17, 2026 (20 to 27 April 2026)

The five charts below summarise what the diamond market did during 20 to 27 April 2026. Each is a static image you can save or share. Together they cover where prices sit today, how inventory is moving, the lab-grown versus natural mix, where retailers raised or cut prices, and how much the same stone can vary across competing sellers.

Lucy Market Index

Ten numbers I record every snapshot.

Versus Week 16, 2026

Biggest shape movers

How the Lucy Market Index has moved

By origin

Top shapes by new listings

Notable stones

Each stone links to its full Carat Hunter listing.