Drilling at the Mt Bonnie deposit intersected zinc, gold and silver mineralisation in 15 holes outside the existing mineral resource envelope.
Mineralisation has been extended below the pit design and both up and down-dip to the existing resource.
Best result was 4 metres at 6.14% zinc, 1.14 g/t gold, 176 g/t silver, 1.29% lead and 0.11% copper from 73 metres, including 2 metres at 10.28% zinc, 1.92 g/t gold, 304 g/t silver, 2.11% lead and 0.17% copper.
James Fox, managing director, said: “Extensions to zinc-rich massive sulphide mineralisation below the existing pit design, and new mineralisation have potential to improve the already strong project economics.
“This would be possible by reducing the mine strip ratio, providing additional ore feed to the proposed process plant and therefore extending mine life.”
Results to be used in definitive feasibility study
In addition to resource extension drilling, the drilling was designed to provide geotechnical, resource, hydrological and metallurgical information for incorporation in the definitive feasibility study (DFS).
The study is due to be completed later in 2018.
In total 65 reverse circulation holes for 3,314 metres, nine diamond holes for 737 metres and one aircore hole were completed.
Other results include 1 metre at 7.68% zinc, 1.48 g/t gold, 305 g/t silver, 1.88% lead and 0.31% copper from 76 metres; 7 metres at 2.24 g/t gold and 81 g/t silver from 88 metres; and 5 metres at 3.28% zinc and 1.37 g/t gold from 35 metres.
Early production schedules supported
Shallow grade control drilling has confirmed near-surface gold-silver rich mineralisation to support early production schedules.
Fox said: “Since the PFS was published in mid-2017, an ideal site to construct process and tailings management facilities has been acquired, debt has been eliminated and there has been considerable improvement in spot commodity prices.
“Current zinc spot prices of US$1.57 per pound are +34% higher than the PFS average price used of US$1.17 per pound.
“Forward price updates along with ongoing project optimisation will be incorporated into the DFS.”
The Hayes Creek project is 170 kilometres south of Darwin.
Hayes Creek comprises the Iron Blow and Mt Bonnie zinc-gold-silver deposits, less than 3 kilometres apart within the Pine Creek region.
PNX recently executed an agreement with a subsidiary of Kirkland Lake Gold Ltd to acquire four mineral leases at Fountain Head, thus securing the preferred site for the proposed processing plant and tailings facility.