Alto Metals boosts Sandstone gold resource by 92%
Gold explorer Alto Metals (ASX: AME) has announced a major boost to the mineral resource estimate of its flagship Sandstone gold project in Western Australia following infill and step-out drilling completed over the last two years.
The new total combined in-pit indicated and inferred mineral resource stands at 12.4 million tonnes at 1.6 grams per tonne gold for 635,000 ounces of gold, representing a 92% on the previous resource estimate released in May 2020.
Importantly, Alto managing director Matthew Bowles said this new figure is being viewed as an interim upgrade with strong potential to continue to grow the resource inventory through further drilling.
“There is significant scope to delineate additional shallow, high-grade gold ounces with the current and planned drilling at the Lords Corridor, Vanguard and Indomitable,” he said.
The latest resource update includes: a 145% jump in Lord Nelson resources to 5.3Mt at 1.6g/t for 267,000oz gold; a 30% higher resource for Lord Henry at 1.9Mt at 1.4g/t for 90,000oz gold; the Vanguard Camp resource tripling to 2.3Mt at 2g/t for 150,000oz gold; and a 119% increase at Havilah Camp to 1Mt at 1.5g/t for 46,000oz gold.
Resource estimates for the Indomitable Camp and Ladybird deposits remain unchanged, although Alto said Indomitable is expected to be included in the next resource update planned for later in the year.
Shallow, high-grade resource remains open
The Sandstone project’s mineral resources are constrained within $2,500/oz optimised pit shells at a 0.5g/t gold cut-off and more than 90% of the total ounces lie within 160 metres from surface.
Preliminary gold recovery testwork has also revealed excellent gold recoveries of around 96% in fresh rock, which Alto says demonstrates the gold will be recoverable through a simple cyanide extraction process.
According to Alto, the shallow, high-grade resources remain open along strike and at depth at all deposits.
Major drilling campaign launched
Mr Bowles said the fact that Lord Nelson’s resource has more than doubled and Vanguard has tripled in size has given the company the confidence that it can materially grow the resources beyond what is currently defined at Sandstone.
“The company remains focused on adding further ounces with extensional drilling and plans to mobilise additional rigs to fast-track this resource growth and also test a number of our high-priority regional targets,” he added.
This additional drilling is already underway, with Alto earlier in the month announcing the start of a major 60,000m drilling campaign at the Sandstone project.
An initial 18,000m of reverse circulation drilling is proceeding to target resource growth and high-grade depth extensions at Lord Nelson, Indomitable and Vanguard.