Highlands Pacific has confirmed the presence of a new copper-gold porphyry (variety of igneous rock known for its hardness and durability) in the Star Mountains, Western province, near the established infrastructure of the Ok Tedi copper gold mine, The National reports.
The final assays from its 14-hole diamond drilling programme at the Olgal prospect returned the highest copper and gold grades to date of 294 metres at 0.67% copper and 1.16 grams per tonne (g/t) gold from 320 metres.
This was part of a wider 596 metre intersection at 0.61% copper and 0.85g/t gold from 24 metres.
The company added the hole 14 mineralisation appeared to be hypogene porphyry copper‐gold, demonstrating that as well as the porphyry and skarn targets, stand-alone porphyry targets in the Tifalmin porphyry copper district could yield the more than 1% copper grades that it was seeking.
Highlands Pacific noted that of the 14 holes drilled at Olgal, 12 have encountered copper and gold mineralisation.
It added the programme had also increased its conceptual understanding of the area and the interplay between more than a dozen targets it plans to test.
The Star Mountain leases consist of Tifalmin (EL1392), Mt Scorpion (EL1781) and Nong River (EL1312).
Highlands Pacific holds a 100% interest in the first two while Nong River is subject to a joint venture agreement with Xstrata Copper where it has the ability to earn a 72% interest in the joint venture by producing a feasibility study by 2019.
While Highlands Pacific is currently sole funding the exploration programme, Xstrata also has the right to reclaim a 72% interest by paying three times the exploration expenditure incurred by Highlands at the time Highlands presents a prefeasibility study.