(Adds details on realised price for manganese ore, review of smelter and impairment charge)
July 20 (Reuters) - South32 Ltd S32.AX on Monday posted a smaller-than-expected drop in fourth-quarter manganese ore output and said it would book a near $100 million non-cash impairment charge on its manganese alloy smelters owing to lower economic viability.
The world's largest producer of manganese ore produced 1.23 million wet metric tonnes (wmt) of the commodity in the quarter ended June 30, compared with 1.29 million wmt a year earlier. The result comfortably beat a UBS estimate of 950,000 wmt.
Prices of manganese, used in glass and steel making, as well as paint, have fallen across the quarter amid the coronavirus pandemic.
South32 said its average realised price for external sales of Australian manganese ore was a 7% discount to the high grade 44% manganese lump ore index in 2020.
While its Australian manganese output remained robust, ore output from South Africa operations fell 35% in the quarter, as virus-prompted restrictions disrupted logistics and halted or slowed mining, as warned earlier.
Following a review, South32 said it had decided to put its manganese alloy smelter Metalloys in South Africa on temporary care and maintenance, while a review of its other smelter, TEMCO in Australia, has been temporarily delayed due to the pandemic.
The miner said it would book a post-tax, non-cash impairment of around $95 million in its 2020 financial results on both smelters.