St George Mining has unearthed a raft of nickel sulphide targets at its Mt Alexander project near Leonora including a large electromagnetic conductor that has been identified as a priority drilling prospect.
The company is currently conducting fixed loop electromagnetic surveys combined with seismic data to pinpoint a series of anomalies identified earlier last month.
The fixed loop electromagnetic survey has identified a large conductor, dubbed by the company “P1”, roughly 4km south of the Cathedrals nickel-copper-platinum group elements massive sulphide deposit on the Cathedrals Belt.
The P1 prospect returned an electromagnetic conductivity reading of 7650 Siemens covering a 400m by 200m area from roughly 200m below the surface.
The company says P1 occurs south of a large, distinctive seismic reflector with an interpreted source below the granite intrusion and bounded by faults possibly related to the Cathedrals massive sulphide mineralisation. The area has not seen any previous exploration and will be a high priority for drilling when the next program begins in coming months.
Four additional conductors have also been identified at a shallower depth than P1. However, the new targets also have a lower level of conductivity and the company hopes further surveys will identify additional zones yet to be fully defined.
St George Mining Executive Chairman, John Prineas said: “The prospectivity of the key conductive anomaly identified by the earlier moving loop ARMIT EM survey has been upgraded. The FLEM data indicates a larger and more conductive anomaly, referred to as P1, that has a geophysical signature consistent with massive sulphides.”
The company says a seismic survey along the Mt Alexander Belt identified a large reflector interpreted to be flat-lying with a strike of approximately 1000m at varying thickness. However, the fixed loop electromagnetic survey did not identify any anomalies coincident with the seismic reflector. St George says this could be because the reflector at 500m below surface is beyond the depth penetration of the survey.
In addition to the large number of nickel sulphide targets, the explorer has identified an increasing number of pegmatite outcrops in its field mapping efforts across a 15km zone of pegmatite dykes at Mt Alexander. A further 119 rock chip samples from the prospective pegmatites have been collected and based on visual observations, St George says a number of samples appear to include lithium minerals in the form of spodumene and lepidolite.
In addition to its own preliminary field work, the company’s review of historical nickel-focused drilling at Mt Alexander has revealed significant intervals of pegmatites that were never assayed.
St George says Mt Alexander is known to host high-grade nickel in other parts of the Yilgarn Craton, including the Flying Fox and Spotted Quoll deposits at Forrestania.
The Cathedrals, Stricklands, Investigators and Radar discoveries are part of a joint venture between St George and IGO subsidiary Western Areas.
The company says its upcoming drill program will test the newly identified nickel sulphide targets in addition to the emerging lithium prospects at Mt Alexander.
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By Matt Birney
