The most opaque corner of the trade — and the most alive. The gemstone desk tracks auction results from Zambian emerald and Mozambican ruby tenders, the cutting rooms of Bangkok and Jaipur, treatment disclosure fights, and the collector demand pushing top stones past diamonds.
Untreated Burmese rubies, Kashmir-quality sapphire and vivid Colombian emerald keep setting per-carat records. Scarcity is structural: the great mines are old and the new finds are small.
A ruby's passport matters as much as its color. Lab reports naming Mogok or Kashmir multiply value — which makes origin science, and origin fraud, the desk's permanent beat.
Producer tenders in Zambia and Mozambique now set benchmark rough prices with auction transparency — squeezing the traditional dealer margin and professionalizing a famously handshake market.
Emerald, ruby, sapphire — the trio that anchors colored-stone value. Everything else, however beautiful, trades as 'semi-precious' economics with rare exceptions like paraíba and spinel.
Most gems are heated, oiled or filled to improve appearance; the sin isn't treatment, it's silence. 'No indications of heating' on a lab report can multiply a stone's price tenfold.
Labs read a stone's chemistry and inclusions like a birth certificate — Mogok ruby, Panjshir emerald, Ceylon sapphire. It's expert judgment, not barcode certainty, and labs occasionally disagree.
The trade's most contested color term: the pure vivid red, historically Burmese, that marks the summit of the ruby market. Whose lab gets to say it is a running commercial war.
The London sale (4–21 May, reported this week) cleared 36 of 37 lots — 97% by number, 99% by weight — at an average $146.08/ct. Managing director Adrian Banks called demand stable but cautious; a ~10% rupee slide since September 2025 pressured Indian cutters. The company, which posted a $51M loss for 2025, is pacing its ruby offering.
The expedited Section 301 investigation's preliminary findings cover India, Thailand, Sri Lanka and Australia among others, with resolution expected by end-July. A second review spans 16 partners; Brazil's definitive 25% on loose polished color is in force. The temporary 10% global surcharge expires July 24.
A 25% Section 301 tariff effective 12:01 a.m. July 23 layers on the existing 10% for 35% total on cut/polished stones and finished jewelry from Brazil; rough (HTS 7103.10.20/.40) and unwrought precious metals are exempt. A pending 12.5% forced-labor duty would take the stack to 37.5%. JVC's Sara Yood called the metals carve-out broad; polished gets no relief.
The miner's first 'Trade Select' auction — a broader mix of Mozambique ruby qualities plus debut sapphire categories — sold 348,409 of 374,008 carats (93.2%) for $23.1M, 82 of 89 lots. May's higher-quality emerald sale made $26.8M at $146.08/ct with buyers cautious and the rupee ~10% weaker since September.
Effective 6 July; the 1984-founded International Colored Gemstone Association counts ~700 members in 47 countries. Dallow arrives via De Beers, Rio Tinto Diamonds, RJC, Grandview Klein and the Women's Jewelry Association.
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