Dalradian Eyes Curraghinalt Mine Development in Northern Ireland

The Curraghinalt project will use long-hole
retreat mining to recover a gold-bearing quartz
A feasibility study of Dalradian Resources’ high-grade, underground Curraghinalt gold project in Northern Ireland supports development of a mine producing 130,000 ounces per year (oz/y) of gold over its first 10 years of operation. Average total cash costs are estimated at $556/oz, and life-of-mine all-in sustaining cash costs are estimated at $674/oz. Initial capital cost to develop the project is estimated at $192 million, with payback in four years.

The Curraghinalt project is based on an orogenic gold system consisting of a series of moderately to steeply dipping, structurally controlled, high-grade gold bearing quartz-carbonate veins. The feasibility study is based of proven and probable reserves totaling 1.44 million oz of gold and 0.66 million oz of silver in 5.24 million metric tons (mt) grading 8.54 g/ mt gold and 3.9 g/mt silver. The deposit remains open in all directions.

The mine will be accessed by an existing exploration adit and a new ramp to be developed adjacent to the proposed plant site. Annual ore production of up to 511,000 mt is planned from primary longitudinal long-hole retreat combined with some cut-and-fill mining methods, as well as from development along the veins. Sublevels will be established at 18-m vertical intervals, with primary cross cuts spaced approximately 200 m apart to access the 16 mineralized veins in the deposit.

A recent test stoping program successfully demonstrated the long-hole mining method at vein dips ranging between 55° and 75°, with good control of dilution. Curraghinalt ore will be processed using a crush, grind, flotation, and leach flowsheet to recover gold and silver into doré. Extensive metallurgical test work has shown that life-of-mine gold and silver recoveries of 94.3% and 57.9% can be expected at a coarse primary grind size of approximately 80% passing 240 µm.

The Curraghinalt project is located about 100 km west of Belfast and 60 km south of Derry/Londonderry, Northern Ireland, both of which have port facilities. The site is accessible by major highways, with grid power and other services close by. Dalradian President and CEO Patrick F.N. Anderson said, “The Curraghinalt feasibility study outlines a project with high expected profitability and demonstrates the strong economic case for advancing project development … We are particularly pleased that our test-mining showed the viability of mechanized underground mining methods for this deposit and returned consistently higher grades than those predicted by the resource model.”

As featured in Womp 2017 Vol 12 - www.womp-int.com