Alto Metals Ltd (ASX:AME) is close to completing a gold resource estimate for the Havilah deposit within its Sandstone project in WA which will add to the existing resource of 261,000 ounces.
The company aims to define at least 500,000 ounces at Sandstone this year as part of its overall strategy to delineate more than 1 million ounces and re-establish gold mining and milling operations.
Alto has commissioned Dr Spero Carras of Carras Mining Pty Ltd to prepare a JORC 2012-compliant mineral resource estimate, which should be completed by the end of the month.
READ: Alto Metals eyes 1 million+ gold resource at Sandstone to recommence mining
His work includes compiling and reviewing of previous explorers’ data.
This has confirmed that the style of high-grade gold mineralisation at the historical Havilah gold mine is similar to the Vanguard deposit 6 kilometres to the northwest, which hosts a resource of 50,000 ounces.
Havilah, like Vanguard, is within the high-priority ‘Alpha Domain’, supporting Alto’s view that the domain has potential to host a substantial gold deposit.
Sandstone regional geology showing location of Havilah.
Executive director Dermot Ryan said: “The style of mineralisation and grade at Havilah is very encouraging.
“There is a major paleochannel of around 5 kilometres between Havilah and Vanguard, which is yet to be drill tested by Alto. This represents an excellent target area.
“In addition, the drilling data and 3D model suggests that the deposit is open down plunge to the northwest and to the southeast.”
Historical production
Historical records show that production from the Havilah mine area between 1904 and 1929 was about 48,497 tonnes at 21.6 g/t for 33,870 ounces, with the majority of this from 1907 to 1911.
These miners largely stoped out a high-grade footwall zone and left intact a lower grade hanging wall zone of mineralisation which was subsequently drilled by modern explorers.
Between 1980 and 2009, 210 drill holes for 7,240 metres were drilled at Havilah by previous explorers with a maximum drill hole depth of 123 metres and an average maximum depth of only 34 metres.
High-grade results
Results from this work include 7 metres at 20.8 g/t from 2 metres, including 1-metre at 120 g/t from 5 metres; 17 metres at 8.5 g/t from 32 metres; 2 metres at 61.8 g/t from 65 metres; and 3 metres at 37.2 g/t from 8 metres.
Alto has captured and digitised the drilling data and detailed historical underground workings to produce a 3D model of the geology, mineralisation and underground workings.
Maximum gold reported to drill hole collars overlying Alto’s aerial drone imagery.
This model has assisted with interpretation of the mineralisation and targeting of future drilling and will enable the company to account for mined out areas in the resource estimate.
Alto also plans further reverse circulation drilling this quarter to test down-dip/down-plunge extensions to the Havilah mineralisation and potentially expand the mineralised area.
READ: Alto Metals Ltd acquiring rights to shallow gold at Sandstone project
Earlier today Alto announced that it was acquiring the surface prospecting rights at Sandstone from Sandstone Exploration Pty Ltd for consideration of 3 million Alto shares.
The 2-metre Prospecting and Fossicking Rights enable the owner to prospect and fossick for gold down to 2 metres depth from surface.
Alto believes these rights will help it to meet the resource goals for the project in the Murchison region.