As governments around the world set out strategies to ensure security of supply for critical minerals, it can pay for mining firms to reassess old core samples. When the team at AuKing Mining reprocessed historic samples held in storage at their Koongie Park copper-zinc project in north-east Western Australia, they were met with a pleasant surprise: significant anomalies of cobalt, a crucial element in electronic vehicle batteries.
"Koongie Park will always be a headline copper and zinc project," says Paul Williams, CEO of AuKing Mining, "but with cobalt prices ranging from $70,000 to $80,000 per tonne you don't need a lot of the mineral to make it economically viable to include it in the copper concentrate to refineries which will give you credit for it."
While cobalt production is dominated by major mines in the Democratic Republic of Congo, the US Department of Energy considers the material the highest short-to-medium term supply chain risk for the electric vehicles industry. Williams hopes the element can act as a sweetener to a copper-zinc project that is already starting to draw attention thanks to its growing resource and improved metallurgical results.
Koongie Park is situated in the Halls Creek region in the northeastern corner of Western Australia, once the epicenter of the 1880s gold rush. In the 1970s and 1980s it was well explored by major mining firms including Kennecott Copper and BHP Billiton and then by ASX-listed junior Anglo Australian Resources (now called Astral Resources). In total over 50,000 meters of drilling was completed at the project. In February 2022 AuKing Mining secured a 75% interest in Koongie Park following an initial earn-in exploration campaign in late 2021.
That work allowed AuKing to boost the JORC resource estimate at the project by 30% to 8.9 million tonnes including 1.1% copper and 3.67% zinc with 0.16g/tonne gold and 32g/t silver. Almost all resources were shifted from the inferred to the indicated categories. Highlights from the 2021 drill campaign included 124meters @ 1.03% Cu, 1.08% Zn, 1.59% Pb and 105 meters @ 1.94% Cu, 0.76% Zn, 55g/t Ag including 16m @ 10.2% Cu, 1.03% Zn and 316g/t Ag.
"Last year's drilling enabled our geologists to have a greater confidence in the resource estimate," says Williams. "The resource looks very much like a VMS style deposit where there are clusters of mineralized shoots. We're confident there are quite a few others in the area." So far, most drilling has focused on the near-surface Onedin target, which could be the established as an open-pit operation, and at the Sandiego deposit, which is deeper and where the cobalt content was discovered.
While copper and zinc are not specifically included in government critical minerals lists, the production of minerals such as cobalt, germanium and indium usually occur as a by-product of primary copper or zinc mining operations. In addition, due to its vital role in the electrification of energy transition technologies from electric vehicles to wind-turbines means that long term demand for the red metal is expected to rise for the foreseeable future. The price surpassed $10,000 per tonne in early 2022 while Zinc - also used in batteries and electrical systems - reached over $4000 per tonne.
"We're seeing a price cycle in copper and zinc that we haven't really seen before," says Williams. "Koongie Park's previous owners, such as Kennecott and BHP, were looking for elephant sized deposits, but this new price structure makes these kind of deposits more attractive from a development perspective." The focus then for 2022 will be to boost the resource number through an 7,500 meter drill program.
"Before we can get into a serious feasibility study program we need to increase the tonnes and identify additional mineralized zones," he says. "We're sitting on 8.9 million tonnes, but that's on the low side for putting out a study. We really want to get to around 15 million tonnes for a deposit like this. That's when we'll be in a position to significantly accelerate development." The campaign will be overseen by new exploration manager Chris Bittar who previously supervised resource expansion activities at Pantoro's Norseman project, also in Western Australia. One particular target is the Emull prospect in the western area of AuKing's tenure portfolio, into which the firm plans to drill around a dozen holes to a maximum of 250 meters.
But while drill programs and core samples are typically the sort of news flow that piques investor interest, in AuKing's case one of the most important breakthroughs has come in the metallurgical testing labs. Previously Anglo-Australian had faced challenges separating the heavily oxidized material near the surface of the deposit, running to about 90 meters in depth, using traditional flotation and acid-leaching processes. However, with the help of Perth based Accudo Metals' patented ammonia leaching technology, the company announced preliminary metal recovery rates of 75% at Onedin in May 2022.
"In the carbonate areas we're having excellent recovery rates using this process," says Williams. "Ammonia is a lot easier to handle, so the environmental footprint for the mine would be reduced. If we can put something together with this process it would not only benefit Koongie Park, it could have wider applications elsewhere."
The research and development investment put into the technology also benefits from significant rebates from the Commonwealth government. That's typical of a government that understands the importance of the mining industry to the local economy.
"Western Australia is a strong and stable jurisdiction, you won't find a significant change in mining laws any time soon and the local government and regulators are familiar with the industry," says Williams. "Our big focus is building a strong relationship with the traditional owners (TOs), the aboriginal population that make up a substantial part of the population in the Halls Creek region. We want to provide training and employment opportunities for the local TOs wherever possible."
With a population of 1500 and a small tourism industry Halls Creek is linked up to local infrastructure including a major highway, a commercial airstrip and potential for gas-fired and other renewable power sources. With hot stormy summers pushing the temperatures up to the 40-45 degree Celsius range, sourcing water is a challenge that can be overcome by developing water bores and storage projects to take advantage of the heavy rainfall that accompanies the wet season from late November to March.
In late May 2022 AuKing tied up more than $4 million through a capital placement and rights issue, enough to fund the current exploration push. Williams, an experienced Brisbane lawyer who worked in-house for a spell with Mitsui's coal operations, is joined in leadership of the firm by non-executive Chairman Dr Mark Elliott, a 40-year geologist with previously in management positions of several ASX listed mining firms and another 40-year geologist, non-executive director Ian Hodkinson. "We've got the commercial and technical expertise to build up the story to support the exploration results," says Williams. "We're in a Tier One mining jurisdiction, we're attracting attention in the critical minerals space and as we progress our metallurgical test work I expect us to produce a standout Australian resource project."