Exploration and development company Orion Minerals has started fieldwork in the Areachap Belt, in the Northern Cape.

Orion holds prospecting rights across 196.7 ha in the area.

The company on Tuesday reported that ground electromagnetic (EM) surveys and geological mapping over anomalies – resulting from helicopter-borne electromagnetic (SkyTEM) surveys on the Masiqhame and Disawell prospecting rights – started earlier this month.

Orion is targeting both volcanogenic massive sulphide (VMS) zinc/copper and magnetic sulphide nickel/copper/cobalt/platinum-group-elements style mineralisation.

Seventeen SkyTEM anomalies are prioritised as VMS targets. The anomalies are spatially associated with a paleo-seafloor setting as determined from fieldwork and the newly acquired airborne magnetic data.

VMS-style zinc/copper deposits occur on the Masiqhame prospecting right at Kantienpan and Boksputs in the Areachap Group, which hosts Orion’s Prieska zinc/copper deposit.

Ground EM surveying began on May 15 on the Disawell prospecting right, with the first survey, over the 2.6-km-long SkyTEM anomaly at HP3, currently under way.

Two conductive plates, 1.2 km and 1.6 km long were modelled from SkyTEM data at this anomaly. The follow-up work at HP3 is targeting VMS-style mineralisation, with mapping over the area confirming favourable volcanic-related lithologies, including metamorphosed felsic tuffs which form the bulk of outcrops over the anomaly.

In addition, dark, poorly-magnetic chert with traces of pyrite found on the target, are interpreted as a distal exhalative phase of the VMS deposit. Ground EM anomalies will be ranked on geology and conductivity before drilling starts.

Two anomalies (Rok Optel and Area 4) have been selected for priority ground EM follow-up as nickel/copper/cobalt/platinum-group-elements sulphide targets. Both are associated with known nickel/copper sulphide mineralisation discovered by previous explorers.

Preliminary conductors modelled from the SkyTEM data suggest that the targets were not adequately tested by previous diamond drilling.

Further target generation for magmatic sulphide nickel/copper/cobalt/platinum-group-elements mineralisation is in progress, reported Orion, and focuses on new intrusions and extensions to the Jacomynspan intrusive complex, where a mineral resource of 6.8-million tonnes at 0.57% nickel, 0.33% copper and 0.03% cobalt at a 0.4% nickel cutoff grade was reported and classified in accordance with the Joint Ore Reserves Committee code.

Meanwhile, Orion wants to complete a bankable feasibility study for the Prieska project in the fourth quarter, and expand and upgrade the mineral resource, which found 29.4-million tonnes containing 1.1-million tonnes at 3.8% zinc and 365 000 t at 1.2% copper, after 50 000 m of drilling was completed in December.

The Masiqhame and Disawell prospects have potential to operate as satellite deposits to Prieska in the future.