American West Metals (ASX:AW1) reports that it has received ‘excellent’ results following metallurgical test work at its West Desert Project in Utah, USA.
The results demonstrate the development potential at West Desert, with recoveries of 89.9% zinc and 78% copper, and relatively low acid consumptions from the use of traditional sulphuric acid leaching.
Simple sulphide flotation testwork on the ‘high-grade’ zinc sulphide ores within the Main Zone of the project tenement has also returned a 99.4% recovery of zinc, with a zinc feed grade of 23.6%.
It is believed that these results have been recognised as a potential pathway to economic extraction of the oxide ores at West Desert.
Metallurgical testwork was commenced to test the near surface sulphide ores and to confirm the historical work conducted by heap leach experts Kappes, Cassiday and associates (KCA).
Speaking on the results, American West Metals Managing Director, Dave O’Neill said: “We are excited to announce the results of key metallurgical testwork completed on recent drillholes 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.
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 ore body 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.
“This is a breakthrough for the project and will help us unlock the full potential of the large ore body at West Desert.”
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 de-risking 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 options.
Work continues on the maiden JORC compliant resource estimate for West Desert, which we hope to be able to provide an update on shortly.”
The company also notes that the new phase of testwork is consistent with the successful historical testwork, which confirmed the excellent metallurgical properties of the underground sulphide dominant ores.
In addition, the results also support the company’s continued study for a combined open pit and underground development opportunity at West Desert.
The West Desert Project is located about 160km southwest of Utah state’s capital city of Salt Lake City within the heart of the Sevier Orogenic Belt, which is host to the world class Bingham Canyon copper deposit and the Tintic Mining District. The project comprises a total land holding of about 32km-square and currently boasts a ‘higher grade’ core of about 16.5Mt at 6.3% Zn, 0.3% Cu and 33g/t In, with American West Metals owning 100% of all associated tenements.
With results from the metallurgical testwork now received, American West Metals announces that further work will focus on optimising the metal extraction process further, particularly for heap leach potential of the oxide classified ores and will include bulk column testing and variability work.
Reverse circulation (RC) drilling is also planned to acquire material to develop a robust mineralogical model of the open pit.
Images: American West Metals Ltd