The Cracow Gold Operation is Aeris’ second major operation, and the company’s flagship gold asset. It is located 500 kilometres north-west of Brisbane, Queensland, on the traditional lands of the Wulli Wulli People, and about 3 kilometres from the town of Cracow and 50 kilometres from the town of Theodore.
Aeris Resources purchased the Cracow mine from Evolution Mining in June 2020.
Cracow Mine Open Pit Projects
Cracow has been a consistent and reliable operation, producing a total of 1.4 million ounces of high-margin gold since mining began in 2004. The current mine life is out to 2023, however Cracow has a strong track record for replacing ore reserves, and Aeris has a $13 million exploration budget planned to develop the Killarney, Kenneth and Sterling brownfields targets, and the Ballymore, Northwest Corridor and Boughyard greenfields regional opportunities.
Gold mineralisation within the Cracow operation is associated low sulphidation epithermal mineralisation formed along multiple fault structures over the current known footprint of 4 kilometres x 4 kilometres. Along each mineralised structure, higher grade gold shoots form at sites of increased dilation and fluid flow.
Cracow performed well in FY2019. Total gold production was 80,983oz – within the 80,000 – 85,000oz guidance range. An AISC of A$1,272/oz was also in line with guidance of A$1,250 – A$1,300/oz. Full year net mine cash flow was A$36.1 million.
The mine is located, in a highly endowed goldfield with gold mineralisation hosted in steeply dipping structurally controlled low sulphidation epithermal veins. All mining is currently by underground narrow vein methods. There has been historical open pit mines at several locations on the property but no active pit mining. Future production will be from a combination of underground and open pits. The open pit projects being taken forward to pre-feasibility study are;
- Roses Pride pit (extension of an old pit)
- Klondyke pit
- Golden Plateau pit (extension of an old pit)
Underground mine production is from several of the known deposits in the field all connected by underground drives to the one portal at surface. Ore is produced using narrow vein bench stoping, occasional cut and fill stopes, and up-hole retreat benching. Dry rock fill is used as the most common backfill. Where required a cemented rock fill will be placed to allow for pillar recovery. The stoping method is described as Avoca or Modified Avoca depending on the access constraints.
Mining equipment is the diesel powered trackless machinery. Stope loaders are 12 tonne capacity and haul trucks are 60 tonne capacity.
Over a two-year period, to 30 June 2022, Aeris expects Cracow to generate more than $100 million of net mine cashflows at the current gold price, with pro forma Aeris group EBITDA of $272 million to $282 million and pro forma group net cash flows of $137 million to $155 million.
The Cracow processing plant consists of a three-stage crushing circuit, primary and secondary ball milling, pre-leach thickening, fine grinding and conventional cyanidation leaching (CIP). The dorē gold bars produced from the plant are then sold to the ABC Refinery in Sydney.