South32 annual coking coal output up 69%

South32 has reported a 69 per cent jump in full-year coking coal production, beating analyst estimates, as the diversified miner ramped up production at its Illawarra project.

The company, spun off from mining giant BHP Group in 2015, also said it had received bids for its South Africa Energy Coal assets in the June quarter and was currently in talks with interested parties.

Four sources familiar with the matter told Reuters last month that Seriti Resources and a consortium backed by global energy trader Mercuria were among up to six groups to have submitted final bids for the assets.

Coking coal output from Illawarra rose to 5.4 million tonnes from 3.2 million tonnes for the year.

UBS had estimated annual output of 5.3 million tonnes.

South32's Illawarra operations accounts for nearly all of the company's coking coal output.

The Perth-based miner has struggled to keep down unit costs at its Appin and Dendrobium collieries after moving to longwall mining, a method used to extract long panels of coal in a single slice.

South32, the world's number one producer of manganese ore, also said it commenced a review of options for manganese alloy smelters "as changes in market dynamics have reduced the attractiveness of our exposure."