American West Metals continues to put runs on the board after it stumped up a whopping 157-metre intercept of visual zinc and copper massive sulphide mineralisation from its fourth diamond drill hole at its West Desert project in Utah. The company says the rods are still spinning in its quest to expose the full extent of the underexplored resource.
Management says the initial visual results from the latest hole appear to extend the continuity of strong copper and zinc mineralisation along the eastern flank in the main zone of the deposit and remains invitingly open for further probing.
American West’s polymetallic West Desert deposit is considered a skarn and carbonate replacement deposit, or ‘CRD’, thought to have been formed by replacement of carbonate-bearing rocks during contact or regional metamorphism. At West Desert, the catalyst for metamorphism is likely the emplacement of multiple porphyries into the Notch Peak dolomite.
Notch Peak is a geological formation rising almost 3000m above the surrounding countryside in Utah.
A characteristic signature of deposits such as West Desert is the zonation of minerals and metals in the skarn permeating from the porphyry contact.
The single, wide 157m zone of mineralisation was housed in a collective 165m intercept starting from 224m downhole, exhibiting the characteristic zonation of zinc-rich and zinc-copper-rich sulphide mineralisation as the hole cut across the skarn towards the porphyry intrusive contact.
The company says the intercept is similar to other finds within the eastern part of the deposit and could suggest a number of ore lenses merge to form a single, very broad and coherent ore zone.
With samples being expedited to the labs, historical drill holes from the area have returned a tantalising 70.1m at 4.6 per cent zinc from 321.4m that includes higher grade zones of 12.6m returning 9.6 per cent zinc and 5.2m at an impressive 12.7 per cent zinc. Closer towards the porphyry contact, historical intercepts have outlined multiple copper-rich zones returning 16.3m at 1.4 per cent copper, along with 0.46 grams per tonne gold and 28g/t silver.
The fifth hole of American West’s maiden 10 hole diamond-drilling program has started and is probing the eastern extensions of thick, high-grade copper zones intercepted in the first diamond hole. The company says the target zone has seen little historical exploration and believes it could beef up its existing non-JORC copper resource, adding significant tonnage and grade to its growing armoury of transitional energy minerals.
The West Desert poly-metallic deposit includes a historical and foreign resource in excess of 59 million tonnes, including a high-grade core of 16.5 million tonnes grading 6.3 per cent zinc, 0.3 per cent copper and 33 grams per tonne indium. The company has previously reported the resource at the project is open at depth and along strike.
Interestingly, despite many historical drill holes being assayed for silver, lead, molybdenum and gold, this clutch-bag of base and precious metals was never included in the previous resource estimate despite throwing up anomalous intercepts.
Additionally, the relatively unknown metal indium was reportedly only assayed in about one third of all historic drill holes. As one of the least abundant minerals on earth, the obscure metal is used to make indium tin oxide an important component in the manufacturing of touch screens and solar panels.
American West is currently evaluating a variety of development opportunities, including one focusing on mining the high-grade core through an open-pit operation before switching to underground mining at depth.
The West Desert Project area lies 160km southwest of Salt Lake City, Utah. The project lays claim to around 330 acres of private land, more than 300 mining claims and a single state metalliferous mineral lease that collectively account for a total land package of around 32 square kilometres.
The area sits in the fruitful Sevier Orogenic Belt that contains a number of world-class copper deposits, including Rio Tinto’s Kennecott mine, largely considered to have churned out more copper than any mine in history.
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By Matt Birney
