A potential $2.6bn deal to create a ”platinum champion” by combining two of the world’s biggest producers of the metal collapsed on Wednesday, adding to the gloom surrounding a sector that has been among the hardest hit by the global slowdown .

Johannesburg-listed Impala Platinum, the second largest platinum producer, spent the best part of last year in talks to acquire Northam Platinum, the fourth biggest, and its major shareholder, Mvelaphanda Resources, which is controlled by a leading South African black investment group.