The Eloise Copper Mine is located in North Queensland, 60 kilometres SE of Cloncurry and 155 kilometres ESE of Mt Isa. The mine has an extensive production history. It was commissioned in 1996 and has since mined over 13.5Mt of ore grading 2.8% Cu and 0.8g/t Au to produce 350,000t Cu and 180,000oz Au in concentrate.
Current operations consist of an underground mine accessed via decline. The upper levels of the mine (above 1,190m below surface) are extracted by longhole open stoping and the lower levels are extracted by sublevel caving.
Mineralisation is hosted within a strongly foliated meta-sedimentary sequence comprising arenites and schists. The metasediment sequence also contains a coarse-grained amphibolite body possibly representing an early intrusion of gabbroic composition. Mineralised zones occur as steeply plunging lenticular bodies with strike lengths between 100m and 200m and attaining a maximum width of 25m. The main zone of mineralisation (Levuka-Eloise Deeps) demonstrates continuity down plunge over 1,500 m and remains open at depth.
The copper at Eloise occurs predominantly as chalcopyrite. Copper mineralisation occurs as either massive sulphide lenses or stockwork veins. Gold is located on the grain boundaries or as inclusions in sulphides and is associated with chalcopyrite, pyrite, pyrrhotite and magnetite.
Processing is via conventional crushing, grinding and sulphide flotation with capacity to treat 725,000tpa. Power for the processing plant is provided by an on-site diesel power station. Metallurgically the ore is very consistent as the ore mineralogy at Eloise is almost exclusively chalcopyrite. Processing achieves high copper recoveries (94% – 95%) and produces a clean concentrate. The concentrate has significant by-product credits from gold and silver.
Ore Reserves at Eloise total 2,198,000 tonnes containing 52,600 tonnes of copper and 43,100 ounces of gold as at 31 December 2022.
Mineral Resources at Eloise total 5,704,000 tonnes containing 137,200 tonnes of copper and 118,800 ounces of gold (inclusive of Ore Reserves) as at 31 December 2022.
Exploration and resource definition drilling at Eloise has been successfully replacing mining depletion each year.
Mineral Resources at Jericho, located 4 kilometres southeast of Eloise, total 9,843,000 tonnes containing 180,000 tonnes of copper and 110,600 ounces of gold as at 31 January 2023. The Jericho Mineral Resource remains open along strike and at depth.
Jericho mine development studies and Eloise processing plant expansion studies are currently underway. Development is expected to commence in 2024 subject to permitting.
Development of Jericho will transform Eloise into a true cornerstone asset for AIC Mines. It will increase production, reduce operating costs through economies of scale, increase the project life and de-risk production by increasing the number of available ore sources.
Significant Exploration Upside
Outside of the Eloise mine, the broader project area hosts three deposits with known resources – Jericho, Sandy Creek and Altia.
AIC Mines’ exploration strategy for Eloise is focused on both extensions to the known resource areas and the discovery of new satellite lodes within the highly prospective 2,000 square kilometre tenement package.