Name of the Mine
Eloise mine.

Location  
North Queensland, Australia, 60 km south-east of Cloncurry and 155 km east-south-east of Mt Isa.

Mine Owner/s  
AIC Mines.

Brief Description  
Eloise is a midscale underground mine using conventional stoping techniques for ore production.

The development of the Jericho deposit will be transformational for Eloise.

Brief History  
The Eloise deposit was discovered by BHP in 1988 and was acquired by Amalg Resources NL in 1994. Following a programme of resource confirmation drilling and metallurgical testwork, Amalg started the mine decline in 1995, followed by ore production in 1996. 

The mine was subsequently divested to Barminco, now FMR Investments, in June 2004. AIC Mines entered into a binding agreement to acquire the mine from FMR Investments in August 2021.

Primary Metals/Minerals  
Copper/gold/silver.

Secondary Metals/Minerals  
Not stated.

Geology/Mineralisation  
Eloise occurs within the Mesoproterozoic Eastern Fold Belt of the Mt Isa Inlier.

The deposit is hosted by a sequence of arenitic metasediments and ortho-amphibolites of the Soldiers Cap group under 60 m of flat-lying Mesozoic sediments

Copper/gold mineralisation occurs predominately within the arenite formations associated with a major shear zone.
Mineralisation occurs as either massive sulphide lenses or stockwork veins.

The main copper-bearing sulphide at the mine is chalcopyrite, with pyrrhotite as the dominant gangue sulphide.

Mineralisation occurs in two corridors, the eastern Levuka to Eloise Deeps and the western Macy to Emerson. They strike north-north-east and dip steeply east.

The eastern corridor demonstrates continuity down plunge more than 2 000 m and remains open at depth.

Mineralised lenses occur as steeply plunging lenticular bodies disrupted by up to eight post mineralisation fault systems, creating a series of mineralised blocks with dimensions of more than 400 m in strike and attaining a maximum width of 25 m.

Reserves  
Total proven and probable reserves as at December 31, 2023, were estimated at 2.45-million tonnes grading 2.4% copper, 0.6 g/t gold and 8.8 g/t silver.

Resources  
As at December 31, 2023, Eloise had total mineral resources estimated at 6.2-million tonnes grading 2.5% copper, 0.7 g/t gold and 9.9 g/t silver.

Type of Mine
Underground.

Mining Method  
Longhole open stoping is used in the upper levels – Levuka, Macy and Elrose Levuka North. A combination of longitudinal sublevel caving and longhole stoping with rock fill is used for extraction of the Deeps mineralisation.

Major Infrastructure/Equipment  
AIC Mines owns and operates the underground production fleet, and a contractor conducts all underground development.

The underground fleet comprises trucks, loaders, a chargecar, a grader, wheel loaders and a stores truck.

AIC Mines’ surface fleet comprises a crane, loaders, a run-of-mine loader, 
A cons loader, a batch plant, a skid steer, an excavator, wheel loaders, forklifts, a fire truck, buses and a service truck.

The mine includes a conventional 725 000 t/y concentrator with three-stage crushing, primary and secondary ball milling; three-stage flotation (rougher, scavenger and cleaners); and dewatering to produce a copper/gold/silver concentrate. 

Prospects  
AIC says the development of the new Jericho deposit will transform Eloise into a cornerstone asset, increasing production to more than 20 000 t/y copper and 10 000 oz/y gold in concentrate. Jericho has similar host rocks and mineralisation to Eloise and is located only 4 km from the Eloise processing plant.

The development of Jericho will reduce reliance on the Eloise Deeps, thereby derisking ore production and the mine plan.

Contact Details 
AIC Mines
Email info@aicmines.com.au

Sources
AIC Mines. Website: https://www.aicmines.com.au/