Williamson Diamonds Limited

Williamson Diamonds Limited operates the historic Williamson Mine in Mwadui, Shinyanga—the world's oldest continuously operating open-pit diamond mine. Founded in 1940 by Dr. John Williamson, the mine is globally renowned for its high-quality gem diamonds, particularly its rare 'bubblegum' pink diamonds. In May 2025, the company underwent a major ownership transformation, transitioning from a majority stake held by London-listed Petra Diamonds to consolidated Tanzanian ownership. Pink Diamonds Investments Limited, an affiliate of Taifa Mining (Tanzania's largest mining contractor), acquired Petra's entire 75% interest, effectively bringing the mine back to local control. Today, WDL is a vital economic pillar for northern Tanzania, managing a 146-hectare kimberlite pipe with resources estimated to last until 2031 and beyond. The company is currently focused on modernizing operations through AI-driven mineral analysis and restoring land through reforestation following a major tailings storage facility incident in 2022.