Petra Diamonds exits Tanzania's Williamson mine after years of trouble

Petra Diamonds has concluded the sale of its remaining 31.5% interest in the Williamson diamond mine in Tanzania to Pink Diamonds, which already held the majority stake, bringing to an end Petra's 16-year involvement in one of East Africa's oldest diamond operations.

Under the terms of the deal, Petra stands to receive up to $16 million, a figure that includes repayment of shareholder loans owed to it by the Williamson joint venture. Rather than a lump sum, Petra will be paid through 20% of the mine's annually generated distributable cash flow until the full consideration has been settled, with proceeds earmarked for general corporate purposes.

A troubled asset

Williamson, near Shinyanga in northern Tanzania, has weighed on Petra's operations for years. Production was suspended in 2022 following a tailings dam breach, the company paid a £4.3 million settlement in 2021 over allegations involving clashes with illegal miners, and the Tanzanian government seized diamonds from the mine in 2017 amid a dispute over export valuations. Those incidents made Williamson one of the more reputationally fraught assets in Petra's portfolio, even as its flagship Cullinan and Finsch mines in South Africa continued to dominate the group's output.

Thanks to Tanzania, focus on South Africa

Petra's joint interim chief executive, Vivek Gadodia, said the company had concluded it was preferable for Williamson to move to consolidated ownership under Pink Diamonds, adding: "We would like to thank the Government of Tanzania for their partnership and support since Petra acquired its interest in WDL in 2009."

The exit lets Petra concentrate management attention and capital on its two remaining South African mines at a time when both are under severe pressure from weak rough diamond prices. It also removes a source of legal and operational risk from the balance sheet just as Petra was working through a broader refinancing of its debt.

What it means for Tanzania

For Tanzania, the sale hands full control of one of its most storied mineral assets to Pink Diamonds, a smaller and less scrutinised operator, at a moment when the global diamond industry is contracting rather than expanding. Williamson's fortunes will now depend on a buyer with a far smaller balance sheet than Petra's, in a market where smaller diamonds — the mine's traditional strength — have suffered the sharpest price declines.

Sources

• Miningmx: Petra Diamonds concludes exit from Williamson mine, 15 May 2025

Photo: Shinyanga, the northern Tanzanian town near the Williamson diamond mine. Tumain1 John, Wikimedia Commons, CC BY 4.0.