Nickel Industries (ASX:NIC) reported second-quarter ore production of 4.1 million wet metric tonnes, up 4% from the first quarter, according to a Wednesday filing with the Australian bourse.

The company's adjusted earnings before interest, taxes, depreciation, and amortization for mining operations increased 58% to $45.7 million in the second quarter from $29 million in the first quarter, per the filing.

Meanwhile, second-quarter ore sales declined 5% sequentially to about 2.9 million wet metric tonnes as an eight-day suspension of mining operations in early April and associated contractor standby costs of $1.7 million weighed on quarterly performance.

Nickel Industries also reported a unit operating cost for mining operations of $21.90 per wet metric tonne in the second quarter, up 40% from $15.70 in the first quarter.