Phoenix Copper Ltd (AIM: PXC, OTCQX: PXCLF) is an AIM quoted North American focused, base and precious metal explorer and developer, which has carried out a drilling programme and generated a copper, gold, silver and zinc resource on which it is carrying out a feasibility study to bring the historically producing Empire Mine in Idaho, USA, back into production. It is also evaluating the silver and gold resources around three other past producing mines within the 23 km² Empire claims block as well as cobalt in two claims blocks north of Empire in Idaho.
Phoenix's primary operations are focused near Mackay, Idaho in the Alder Creek mining district. This district includes the historical Empire, Horseshoe, White Knob and Blue Bird Mines, past producers of copper, gold, silver, zinc, lead and tungsten from underground mines in the first half of the twentieth century. Additionally, the district includes Navarre Creek, a volcanic-hosted disseminated gold discovery which hosts a 6.1 km gold strike length within a 9.8 km² area.
Phoenix acquired an 80% interest in the historical Empire Mine property in 2017 and, based on a total of 320 drill holes, an oxide resource was completed in late 2017. A NI 43-101 compliant PEA (preliminary economic assessment) for an open pit heap leach solvent extraction and electrowinning ("SX-EW") mine was completed in April 2018. In 2018 a further 8,600 metres in 93 holes was completed to upgrade the oxide resources, provide samples for ongoing metallurgical test work, geotechnical and hydrological studies and condemnation drilling for the heap leach pad site, waste dump and plant site. An updated NI 43-101 compliant resource was completed in early May 2020 and October 2020 for all metals. Present contained metal in all NI 43-101 compliant categories of resources, measured, indicated and inferred, stand at 355,523 ounces of gold, 129,641 tonnes of copper, 10,133,772 ounces of silver and 58,440 tonnes of zinc.
Since acquiring the Empire project, Phoenix has increased the claim area from 818 acres to 5,717 acres, mainly to the northwest and west, and in so doing has increased the potential for additional oxide and sulphide copper resources, as well as the potential for stand-alone gold and silver resources, along a strike length of approximately 5.4 km towards the other brownfield mines of the Horseshoe, White Knob and Blue Bird Mines now within the property boundary. In particular, a new discovery at Red Star, 330 metres north west of the Empire Mine proposed open pit, has revealed sulphide ore and from three shallow exploration drill holes a NI 43-101 compliant maiden resource of 1.6 million silver equivalent ounces was reported.
Phoenix secured an option to acquire an 80% interest in Konnex Resources Inc in 2015. Konnex owns a brownfield, past producing, copper, gold, silver, and zinc underground mine, the Empire Mine, near Mackay in Idaho, Konnex’s only asset. Phoenix completed its AIM IPO in mid-2017, exercised the option and acquired the 80% interest in Konnex.
Between 1901 and 1942 Empire produced direct smelting ore at grades of between 6% and 8% copper and up to 6.6 grammes per tonne gold. Since the mid-1960 drilling on the 3.31 square kilometre property, consisting of patented and unpatented claims, had identified a near surface open pit mineable oxide deposit sitting above the old underground mine workings. Other than this, no modern exploration had been carried out on the property or on the surrounding mineralised area.
In 2017 additional drilling was completed on the oxides with the view to generating resources and reserves on which to develop a low capital and operating cost open pit heap leach copper operation to self-finance the exploration of the surrounding area. In November 2017, an NI 43-101 compliant open pit copper oxide was completed. Then in April 2018 additional contiguous claims were staked to encompass three other old mine workings and the property was expanded to 7.18 square kilometres.
Following mining, metallurgical, infrastructure and environmental studies a Preliminary Economic Assessment ("PEA") on an open pit heap leach solvent extraction and electro-winning ("SX-EW") copper project was also completed in April 2018. In June 2018 five drill rigs embarked on a drilling programme to increase the oxide resources. An additional 8,600 metres of drilling was completed by year end bringing the total drilled in an 18-month period to 11,650 metres in 126 holes. Additional metallurgical heap leach column tests were carried out as well as geotechnical, hydrological and environmental studies.
In February 2019 the property was expanded further to encompass two areas. The area around the Empire Mine was increased to 13.34 square kilometres and includes more than 30 historical prospects, shafts and adits with an overall length of contiguous mineralisation of some 5.4 kilometres. Also staked is the Navarre Creek property, some 6.5 kilometres west of Empire, over a 9.8 square kilometre area geologically similar to the Carlin Trend gold belt in Nevada suggesting excellent potential for precious metal discoveries.
In October 2020 an updated resource model, resulted in “Measured and Indicated” resource of 22.9 million tonnes ore, with 10.6 million tonnes of “Inferred” resource, giving an overall metal content of 129,641 tonnes of copper, 58,440 tonnes of zinc, 10,133,772 ounces of silver and 355,523 ounces of gold. During the 2020 evaluation programme, gold was successfully recovered in the laboratory from the Empire Mine ore using the environmentally friendly reagent ammonium thiosulphate.
The total 23.14 square kilometre property could, according to Phoenix’s consulting geologist, host a world class porphyry copper/gold deposit. At the same time early production can be achieved from the “Measured and Indicated” oxide resources already identified.
The Company is now completing an updated PEA on the open pit oxide project, which will outline the development strategy for a low capital cost, open pit mine, producing copper, gold, silver and zinc.
A new zone of surface mineralisation in the Empire block, now named Red Star, was discovered during the 2018 drilling programme, located 330 metres north-northwest of the Empire oxide pit. Three drill holes into the zone returned assays of high-grade lead and silver sulphides including intercepts of 20% lead and 39.4 ounces of silver per tonne and in 2020 further 10 drill holes have expanded the project’s resource and exploration potential. Red Star represents an exciting near-surface sulphide exploration prospect.
The results from two 2017 deep diamond drill holes confirmed the presence of higher-grade sulphide mineralisation in the skarn structures at depth below the Empire Mine historical workings.
Both core holes intersected mineralised skarn over much of their length and the analytical data from both drill holes intersected numerous significant intervals of copper, gold, silver, zinc, lead, and tungsten throughout their depths.
The tungsten values were particularly interesting as they positively reinforced the Company's consulting geologist's predictions of the Empire system hosting significant values of tungsten at depth. Following a site visit In April 2019, Nigel Maund, the Company’s consultant geologist, completed an update of his 2015 geological report of the Empire Mine. Amongst his conclusions, he confirmed that the Empire Mine comprises a world class polymetallic ore system containing tungsten and molybdenum, as well as copper, gold, silver, zinc and lead. He also concluded that the mine is sited along a major north south structure, with some five kilometres of geologic strike (of which the footprint of the heap leach open pit copper project is one-kilometre). Furthermore, he reported that exploration has to date focused on the near surface oxides in the proposed open pit and concluded that only 1% to 2% of the ore system has been tested to date.
Borah Resources is a 100% Idaho registered subsidiary of the Company. Given the world's growing need for battery metals and cobalt in particular the Company’s Redcastle and Bighorn properties represent a timely acquisition, strategically located in the USA's only prospective cobalt region, the Idaho Cobalt Belt, approximately 100 miles north of the Empire Mine.
With a management team that has successfully constructed, commissioned and operated mines, a low risk mining-friendly jurisdiction and excellent infrastructure, Phoenix is looking to fulfil its ambitions to become a mid-tier base metal and precious metal producer.
With 23.14 square kilometres of highly prospective claims it will apply modern exploration techniques to find the world class porphyry deposit at the same time.