Phoenix Copper upbeat on testing results from Empire Mine

The AIM-traded firm said the tests were conducted in partnership with Resource Development and Forte Dynamics, based in Wheat Ridge, Colorado.

It said the findings indicated the viability of recovering copper, gold, and silver through non-cyanide leaching technologies.

The comprehensive tests conducted by Forte involved a series of processes including crushing, grinding, flotation, and leaching with sulphuric acid and ammonium thiosulfate (ATS).

Those procedures were performed on drill core composites obtained from the Empire Mine's 2022 metallurgical core drilling programme.

Forte not only tested ATS as a sole reagent for the mine material, but also developed flow sheets for two hybrid processes - one involving flotation followed by sulphuric acid leaching, and another involving flotation followed by ATS leaching to extract gold, silver, and copper.

The results thus far had identified two possible methods warranting further study for metal recovery - the flotation plus ATS process, and the flotation plus sulphuric acid leach process.

According to the company, both proposed leaching circuits would be housed in agitated tanks.

The next steps for Forte included optimising the identified processes, and incorporating operating and capital costs in the optimisations.

“The results of the metallurgical test work completed thus far on the Empire open pit oxide deposit have further solidified the company's confidence in the project,” said chief executive officer Ryan McDermott.

“When Phoenix became involved with Empire in 2017, the Empire Mine was considered a copper project only.

“As a result of further drilling and test work conducted since that time, the Empire Mine has evolved into a robust polymetallic deposit consisting of copper, gold, and silver.”

McDermott said the recent metallurgical results showed that a number of processes exist, allowing for the recovery of all three metals.

“The flotation process is an industry standard for the metal extraction of sulphide copper deposits.

“By taking the time to test this process on Empire's oxide material, we believe we have set ourselves up for success both in the short and medium term.

“We are continuing down this path with the expectation that a flotation-based process will further improve the economics and environmental, social and governance credentials of the Empire open pit, while potentially streamlining the later development of the company's deeper underground sulphide mineralisation.”

Additional optimisation and costing of the flotation, plus leaching scenarios, would define the best process design for the Empire open pit, Ryan McDermott added.

“Continued test work and mine plan development will also determine whether it will be possible for the company to minimise the project's footprint by constructing the agitated leach tanks on private property adjacent to the pit, which may offer significant environmental and economic benefits.

“The results of the continuing optimisation work are anticipated in the fourth quarter of 2023.”

McDermott also said he was pleased that the drilling campaign on the company’s Navarre Creek property was well underway.

“Thus far, we have drilled a total of 9,825 feet.

“We anticipate initial drill hole assays to begin arriving from ALS Laboratories beginning early in the fourth quarter.”

At 1055 BST, shares in Phoenix Copper were down 0.86% at 23.05p.

Reporting by Josh White for Sharecast.com.