Global mining major Rio Tinto is planning to raise about $250m in a separate listing of its diamonds unit on London Stock Exchange after the company failed to find a potential buyer for the unit.

The floatation, which is code-named ‘Project Aurora,’ is expected to be carried out before this autumn, reported Sky News.

The mining giant has appointed Morgan Stanley (MS) to oversee the IPO in London.

Since March 2012, Rio Tinto has been looking to offload its assets saying that they are not in line with its strategy.

Rio’s diamond division is the third-biggest producer of rough diamonds worldwide. It operates mines in Canada, Zimbabwe and Australia, and owns a cutting and polishing factory in Perth to process the rare pink diamonds from its Argyle mine.