Global mining giant BHP Billiton says it has agreed to sell its stake in South African mineral sands venture Richards Bay Minerals to partner Rio Tinto, signalling its exit from titanium.

“BHP Billiton has exercised an option to sell its 37 per cent non-operated interest in Richards Bay Minerals (RBM) to Rio Tinto and will exit the titanium minerals industry,” it said in a statement on Wednesday which gave no price.

RBM is a South African mineral sands mining and smelting operation and the leading producer of chloride titanium feedstock. Rio Tinto manages the operation and is responsible for the marketing of RBM’s products.

The deal will see Rio Tinto’s stake double to 74 per cent. Black South African investors own a 24 per cent holding and employees the remaining two per cent.