Geophysical surveying that accurately mapped known sulphide mineralisation at Si6 Metals’ Maibele North project in eastern Botswana has also defined several new nickel-copper sulphide targets along strike from, and below, the project’s 2.38 million tonne resource grading 0.72 per cent nickel and 0.21 per cent copper. Si6 is considering a drill campaign to test the new targets.
The company has been using geophysics to identify deeper sulphide targets for drill testing at 60 per cent owned Maibele North, Airstrip and Dibete at its Maibele nickel-copper project.
The resource at Maibele North covers 800m of strike with nickel-copper sulphide mineralisation said to continue for a further 475m to the north-east and 125m south-west. The deposit is also open at depth.
The latest audio-frequency magnetotellurics or “AMT” survey covered the entire Maibele North mineralised envelope and its strike extensions.
Management says numerous untested anomalous zones have been detected beneath the resource, predominantly below thicker zones of mineralisation.
Maibele North has seen next to no drilling at deeper levels with the current resource defined to depths above 250m. However, two past holes about 400m to the east of the resource intercepted sulphides below 400m depth.
One historical hole delivered 6.82m at 0.75 per cent nickel and 0.25 per cent copper from 460m. Intriguingly, management says the AMT survey detected a large, strong anomaly corresponding to the intercept.
Another nearby hole returned 0.42m at 0.12 per cent nickel and 0.08 per cent copper from 444m. The hole is interpreted to lie on the periphery of the newly identified large anomaly.
Si6 Executive Chairman Patrick Holywell said: “Through our targeted approach, which utilises various ground geophysical techniques to target deeper mineralisation, we are really starting to gain a better understanding of what we are dealing with and, in turn, plan our future drilling programs in more detail. We anticipate following up the AMT targets with a combination of reverse circulation and diamond drilling, in addition to planning for further AMT surveys to the east and west of the current survey area.”
The survey also took in part of the nearby Airstrip prospect to the south-west where historical drilling returned some eye-catching hits including 8m at 10.39 per cent copper and 630 grams per tonne silver from 52m.
Management reports a small, strong response from the survey at depth suggesting potential for a deeper source of the mineralisation at Airstrip.
Si6 believes the new anomalies at Maibele North and Airstrip are likely to represent sulphide mineralisation and the company has commenced discussions with local drilling contractors as it builds a plan to test the targets.
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