FOLLOW-UP drilling by the Minotaur Exploration and OZ Minerals joint venture at the Iris-Electra copper-gold prospect near Cloncurry in north Queensland has confirmed the potential for copper sulphide mineralisation. All four holes of the program intersected hydrothermally altered breccia zones exhibiting various degrees of chalcopyrite mineralisation.
The Iris-Electra copper-gold prospect lies under shallow cover about 5km northeast of the Eloise copper-gold mine. The prospect sits along the Levuka Shear Zone within Mt Norna Quartzite, a regionally significant rock unit that hosts the Eloise and Osborne copper-gold mines as well as South32’s Cannington silver-lead-zinc mine. Minotaur’s geological model for Iris-Electra is iron sulphide, copper-gold (ISCG) mineralisation, similar in style to the Eloise deposit.
An accelerated program of four diamond drill holes at Iris was completed by the JV. This followed promising results from the inaugural two diamond holes at Iris which returned anomalous copper and gold values associated with pyrrhotite over broad intercepts, confirming Iris as a significant new ISCG discovery.
Those results prompted the JV to place a further four drill holes into the Iris conductors. These holes utilised existing heritage-cleared drill pads for expediency.
Significant intersections from the latest round of drilling include 20 metres from 228 metres @ 0.18% copper and 0.03 g/t gold, and 5.8 metres from 277 metres @ 0.48% copper and 0.06 g/t gold; 26 metres from 168 metres @ 0.73% copper and 0.61 g/t gold, including 0.4 metres from 175.3 metres @ 12.35% copper and 14.3 g/t gold; 40 metres from 390 metres @ 0.25% copper and 0.06 g/t gold, including 12 metres from 409 metres @ 0.52% copper and 0.17 g/t gold; and 36 metres from 154 metres @ 0.2% copper and 0.09 g/t gold.
Copper-gold mineralisation is now documented along 600 metres of strike, reinforcing the potential scale of the mineral system.
The persistent nature of mineralisation in the drilling indicates a large mineral system with potential for higher grades in the vicinity of the EM conductors. Mineralisation is open in all directions and the in-fill ground EM grid completed over the Electra EM anomalies shows conductive bodies modelled along 2.7km of strike.
The results have given the JV sound reason to continue drill testing. Field activity will diminish during the wet season, until March 2017 and it is anticipated drilling will recommence around that time.