HB Antwerp Urges Diamond Industry to Scrap Auctions for Profit-Sharing Model Amid Price Crisis
The global diamond market is facing one of its deepest crises in history, with producers struggling against falling prices, weak demand, and growing competition from lab-grown alternatives.
According to Oded Mansori, co-founder and managing partner of Belgian gem trader HB Antwerp, the traditional system of selling rough diamonds through tenders and auctions is outdated, opaque, and leaves producers vulnerable.
Speaking on Thursday, Mansori argued that miners could increase revenues and improve resilience by abandoning inefficient sales systems. “For years, miners relied on tenders and auctions—systems that look efficient on paper but in practice resemble a casino,” he said.
“Rough stones are pushed into opaque markets where value is anyone’s guess. When global demand softens, producers are left exposed. Workers pay the price, while shareholders watch assets decline.”
The downturn has already taken a toll on producer nations such as Botswana, which depend heavily on diamond revenue, and on mining companies including Burgundy and Lesotho’s largest mine, Letseng, which have resorted to job cuts.
Traditionally, rough diamonds are sold through competitive bidding, where buyers place confidential offers for stones or parcels. But Mansori says this model no longer serves producers well, particularly in volatile markets.
HB Antwerp operates a profit-sharing model with Lucara Diamond Corp, tying payments to the final polished value of stones rather than uncertain rough sales.
Under this arrangement, HB Antwerp purchases stones of 10.8 carats and above from Lucara’s Karowe Mine in Botswana at prices based on estimated polished values.
This approach has already delivered results: HB Antwerp accounted for 72% of Lucara’s $74 million in revenue in the first half of 2025, up from 65% a year earlier.
Mansori claims that producers can earn up to 40% more through such models compared to traditional auctions.
With demand for natural diamonds under pressure from both economic uncertainty and synthetic alternatives, producers face growing calls to rethink sales structures.
Advocates like Mansori argue that linking revenues to polished value could help stabilize earnings, protect jobs, and improve long-term sustainability across the diamond supply chain.
