News: S32 UPDATE 1-Australian miner South32's quarterly met coal output falls 50%

(Adds details, context in paragraphs 3-5)

Jan 22 (Reuters) - Australian diversified miner South32 Ltd (S32) on Monday posted a near-50% drop in second-quarter metallurgical coal output, as its Illawarra operation completed two planned longwall moves.

The Perth-based miner said production of metallurgical coal, used to make steel, fell to 744,000 tonnes in the three months to December, from 1.5 mt a year earlier. This is below the estimates of 1.0 mt by Macquarie Group and 1.1 mt by Morgan Stanley.

The company affirmed its annual total coal production forecast for Illawarra operations of 5.0 mt, with volumes remaining weighted to the second half.

South32, the world's biggest producer of manganese, the additive that strengthens steel, reported manganese ore output of 1,272 thousand wet metric tons (kwmt) for the quarter, down from 1,477 kwmt in the year-ago period.

Manganese production for the half year ended in December fell 5%, as lower yields hurt secondary output at Australia Manganese, and its South Africa Manganese operation completed a planned maintenance shutdown at the Mamatwan mine.