American West Metals Limited (ASX: AW1) has received “excellent” results from metallurgical test work on the near surface and sulphide ores at the West Desert Project in Utah.
“We are excited to announce the results of key metallurgical test work completed on recent drill holes from West Desert. The results demonstrate that the mineralisation from a potential open pit and underground mining operation at West Desert is likely to be amenable to commercial processing,” Managing Director, Dave O’Neill, said.
“The test work confirmed that traditional acid leach processing can generate very high metal recoveries from the near surface oxide ores, which would be mined in an open pit operation.
“This is a breakthrough for the project and will help us unlock the full potential of the large orebody at West Desert.
“The new work has also further validated the known excellent metallurgical properties of the sulphide ores in the high-grade Main Zone of the West Desert Deposit with almost 100% recovery of zinc.
“West Desert is blessed with very simple and well understood ore mineralogy with very low deleterious elements. This work has taken a significant step in derisking the project and increasing the available resource tonnages.
“We believe this will give us outstanding development optionality which will allow a staged mining strategy that includes both open pit and underground operations.
“Work continues on the maiden JORC compliant resource estimate for West Desert, which we hope to be able to provide an update on shortly.
Open Pit Potential Highlighted
A number of historical metallurgical programmes have been completed on the West Desert ores and all have demonstrated excellent metallurgical properties and the ability to produce high quality zinc and copper concentrates. However, the majority of these tests were focused on the sulphide portion of the orebody.
A single test on the oxide material was completed in 2009 by Kappes, Cassiday and Associates (KCA) in Reno, Nevada. This work had shown promising results, with excellent recoveries of zinc and copper, and with relatively low acid consumption. This was recognised as a potential pathway to economic extraction of the oxide ores at West Desert.
The aim of the latest phase of metallurgical work was to confirm the historical work by KCA and to understand and optimise the process further. The test programme was completed by BASE Metallurgical Laboratories of Kamloops, BC, Canada.
The recent test work was completed on drill core samples from the 2022 diamond drilling programme and has shown outstanding results that demonstrate the potential viability of the oxide and transitional ores to traditional processing techniques.
The acid leach test work on a range of different sized oxide material has produced up to 89.9% recovery for zinc, 78% recovery for copper, and with relatively low acid consumptions.
Testing of high-grade sulphide ores from the Main Zone of the West Desert Deposit has confirmed historical results and produced exceptional recoveries of over 99% for zinc using simple sulphide flotation.
Heap leaching is widely used as a low cost and simple processing technique and can be used to recover very low concentrations of base and precious metals. The amenability of the oxide ores to this process method unlocks the near surface potential of the West Desert Deposit and supports the potential for a staged open pit and underground mining scenario.
For further information please visit: https://www.americanwestmetals.com/
