Meanwhile, it benefited from strong prices for the commodities.

"Despite 2021 being a challenging year as global industry continued to be impacted by the pandemic, Ramu delivered strong results despite incurring an unplanned outage in [the fourth quarter] due to the pandemic," Nickel 28's chairman Anthony Milewski said.

The company's nickel production in the December quarter stood at 6,368 tonnes, which was down 24% from 8,373t for the same period a year earlier. That took 2021 nickel production to 31,594t, which was down 6% from 33,659t in 2020.

BMO Capital Markets analyst Andrew Mikitchook said the 2021 nickel production was close to BMO's forecast of 32,260t and the investment bank maintained its estimate for 2022 of 32,260t.

Nickel 28's cobalt production in the fourth quarter fell 22% year-on-year, from 745t to 579t. Full-year production was little changed from 2020 at 2,953t, compared with 2,941t.

The miner said the average LME average nickel price was US$8.99 per pound in the fourth quarter, which was a 24% increase from the same period a year earlier. The full-year nickel price averaged US$8.39/lb, which is up 34% year-on-year.

Mikitchook noted that Nickel 28 had benefited from strong prices for the commodities, which helped the company repay the operating portion of its Ramu debt during 2021. The debt payment was ahead of schedule and left US$79 million of Ramu construction debt at the end of the thitd quarter.

On February 2, Nickel 28 traded on the Toronto Stock Exchange at C$1.23/share, which was up 2% from the day prior. The company's share price has trended upwards since mid-2020, when it was trading at less than C$0.20/share.

The miner had a market capitalisation of C$111.71 million.