Copper producer AIC Mines has reported a significant boost to ore reserves at the Jericho deposit, south of its Eloise high-grade underground copper mine in Queensland.
The reserve now sits at 3.2 million tonnes grading 1.9% copper and 0.4 grams per tonne gold for 61,100 tonnes of copper and 37,000 ounces of gold.
It represents an 86% increase on the previous reserve for contained copper and gold and equates to approximately 22% of the total Jericho mineral resource estimate of 14.1Mt grading 2.0% copper and 0.4g/t gold.
Underground mine design
The new figure comes after AIC incorporated a detailed underground mine design consisting of a single surface boxcut, a southern decline accessing the Jumbuck zone and two northern declines accessing the Matilda zone.
It also included results from a 2023 drilling program at Jericho’s J1 Lens, which added 22,400t of copper and 14,300oz of gold.
AIC said further exploration would be required on the less advanced J2 Lens, which added only 5,900t of copper and 2,800oz of gold.
Ongoing underground and surface drilling is expected to further increase the reserve, which remains open along strike and at depth.
Surface drilling will target down-plunge extensions of known high-grade shoots at Jericho as well as the recently-discovered Swagman shoot, located approximately 2 kilometres to the north.
Recent acquisition
Managing director Aaron Colleran said the good news comes just 12 months after the company acquired the Jericho deposit in an off-market takeover of minerals explorer Demetallica.
“It has been an incredibly busy and successful period for AIC… in this time, we have significantly increased the Jericho mineral resource and ore reserve, carried out mining and environmental studies, done some metallurgical testwork and completed an Eloise expansion study,” he said.
“We believe Jericho is a game-changer for Eloise… it provides a pathway to expanding annual production [at the mine] to more than 20,000t of copper and 10,000oz of gold in concentrates and mining costs will be lower as it is a much shallower [deposit] commencing only 50m below cover.”
Eloise production
The Eloise underground mine opened in 1996 and has since produced approximately 350,000t of copper and 175,000oz of gold.
AIC is targeting annual production of approximately 12,500t of copper and 6,500oz of gold in concentrate.
Jericho is located 4km south of Eloise and is expected to increase the mine’s production and lifespan and de-risk the operation by increasing the number of available ore sources.
Mr Colleran said expansion of the Eloise processing plant to accommodate Jericho will reduce operating costs through economies of scale and “smarter” equipment.
