Tiwai Point smelter’s annual net profit plummets amid volatile pricing.

The owner of New Zealand’s sole aluminium smelter says it has delivered a significantly lower profit for calendar 2018 and that it remains vulnerable to a volatile market this year. Pacific Aluminium (New Zealand), which is 80 percent-owned by Rio Tinto with Sumitomo owning the rest, says the Tiwai Point smelter showed underlying earnings of $22 million for 2018, down from $53 million the previous year. “The result reflects that during 2018, the operating environment became significantly more challenging,” the company says. Aluminium prices on the London Metal Exchange averaged US$2,259 a metric tonne in the second quarter but then…