Critical minerals explorer Astute Metals (ASX:ASE) has intercepted thick lithium claystone host rocks during a maiden drilling program at its Altair and Polaris Lithium projects in Nevada, US.
Since drilling restarted at the project, the $16.84 million market capitalisation company reports it has completed its first drillhole at Altair and redrilled a hole at Polaris.
Drillhole AL01, completed at Altair, intersected 109.7m of Siebert formation claystone, including a thick continuous zone of blue-green claystone and clayey gravels from 71.6-181.4m. The company says this is the thickest intersection of the Siebert formation encountered to date by Astute in Nevada.
Astute says the thick intersection of Siebert formation at Altair confirms the presence of prospective lithium host rocks at the project, demonstrating the ‘excellent’ potential for lithium mineralisation.
Meanwhile, the redrill strategy at Polaris has seen hole PL04A intersect 59.5m of Siebert formation, which is considered a ‘significant’ extension beyond the original PL04 intersection of 27.4m that ended in ‘low-grade’ lithium mineralisation of 3.05m grading 140.8 parts per million (ppm) lithium.
The deepening of the claystone intersection in PL04A was designed to test for higher-grade lithium mineralisation beyond this original intersection given the general increase in lithium grade observed towards the end of the hole.
The company says the redrill has ‘significantly’ extended the claystone encountered in PL04A, highlighting the potential of the project area. Astute also notes all drillholes at Polaris and Altair ended in Siebert formation claystones, indicating further potential beyond the extent of current drilling.
Astute reports samples collected from both holes will be dispatched to ALS Laboratories in Reno for analysis, with results expected by mid-September.
The company says the ‘challenging’ ground conditions encountered while drilling the initial sites at Polaris and Altair have led it to demobilise the rig from site to return with a higher-powered rig to complete the remaining holes at Altair. Astute says it has conducted initial discussions with its current drill contractor, which has availability for a higher-powered rig in October 2023.
Commenting on the results, Astute Metals Chairman Tony Leibowitz says: “Our lithium exploration strategy in North America is beginning to deliver some exciting results, with wide intercepts of the prospective claystone host rocks in the first hole at Altair and the redrilled hole at Polaris.
“Our lithium exploration strategy in North America is beginning to deliver some exciting results”
This is exactly what we wanted to see in the drilling and provides significant encouragement that our exploration strategy in this highly sought-after district is firmly on track. We look forward to assays and further results from the drilling.”
The Siebert formation is the local name for lacustrine (lake) sedimentary rocks mapped across parts of Nevada. The formation is known to host 2 of the largest lithium resources in the US, including the 15.8-million-tonne lithium carbonate equivalent (LCE) Tonopah Flats deposit and the 9.79-million-tonne LCE TLC Lithium deposit.
Astute is a Sydney-based critical minerals explorer formerly known as Astro Resources. Across its portfolio of assets in Australia and the US, the company is focused on finding and developing critical minerals for the global energy transition.
Along with the Altair and Polaris projects, Astute also holds the Needles Gold Project in Nevada, as well as the Governor Broome Heavy Minerals Project and Kimberly Diamonds Project in Western Australia, and the Georgina Basin Iron Oxide Copper-Gold (IOCG) Project in the Northern Territory.
On 13 July 2023, Astute reported it acquired the Fouracres property that adjoins its Governor Broome Project for $150,000 and a 1% royalty on future production.
Write to Harry Mulholland at Mining.com.au
Images: Astute Metals NL