ASX-listed market darling Metals X has delivered a 55 per cent jump in ore reserve and increase in underground mine life at its Nifty copper operation in Western Australia.

Copper reserves at Nifty — near Telfer in the East Pilbara region of Western Australia — now stand at 237,500 tonnes compared to a May estimate of 153,500 tonnes.

Current underground mine life at Nifty now stands at around seven years based on current production rates. Based on 2018 targeted production levels of 40,000 tonnes per annum, mine life comes in at around 6 years.

Resources at Nifty stand at 41.58 million tonnes at 1.5 per cent copper for 622,000 tonnes of contained copper.

The revised estimates include 20,000 metres of underground drilling completed by Metals X in early 2017.

“Underground drilling is continuing to identify additional mineralisation that will be incorporate into a proposed further upgrade of resource and reserve estimates in the first half of 2018,” Metals X managing director Warren Hallam said.

“We have no doubt as to the long-term future of Nifty and this is a further step in transforming Nifty back into a large, long life and profitable asset.”

Metals X remains on track to produce 40,000 tonnes of copper at its Nifty copper mine this year.

Metals X (ASX:MLX) shares were trading at 82c Thursday afternoon trade.