Infill drilling at Pacifico Minerals’ (ASX: PMY) Sorby Hills lead-zinc-silver project in Western Australia’s Kimberley has increased confidence levels in the existing mineral resource.
The results are expected to upgrade the current resource of 16.5 million tonnes at 6% lead equivalent (4.7% lead, 53 grams per tonne silver and 0.7% zinc) and materially enhance the economics of the project’s optimised pre-feasibility study due later this year.
A total 72 angled and oriented diamond holes for 5,372m were drilled into numerous targets at Sorby Hills from east to west to test geological structures.
Best results were 11.7m at 13.2% lead equivalent (10.8% lead, 105g/t silver and 0.4% zinc) from 75.7m, and 10m at 7.8% lead equivalent (6.6% lead, 53g/t silver and 0.9% zinc) from 82m.
Pacifico said the campaign clearly delineated between ore and waste and highlighted the course-grained nature of the galena mineralisation favourable for pre-concentration prior to grinding and floatation.
Previous test work has shown the ore can be gravity separated from the carbonate host waste rock.
The company will undertake further test work to confirm the economic viability of various pre-concentration methods over the entire mineralised body.
First discovered in 1971, Sorby Hills has been subject to extensive exploration work over the years and, although major mining companies considered developing the project, its progress was eventually hindered by a lack of infrastructure and a challenging regulatory regime.
Almost four decades later, infrastructure in the east Kimberley has significantly improved with a sealed road now in place to the project, hydropower from the region’s Argyle Dam available to within 30km of the tenements, and the Wyndham Port capable of shipping mineral concentrate to seaborne markets.
Native Title over the project’s mining leases has been extinguished and a state agreement legislates for the development of Sorby Hills alongside the Ord stage II irrigation project.
In October, Pacifico completed the acquisition of a 75% interest in Sorby Hills, with China’s Henan Yuguang owning the remaining 25%.
Both parties contribute proportionately to the project’s development costs.
“We believe the macro-economic factors, improved infrastructure in the Kimberley, new processing technologies, an improved lead price outlook and lower exchange rate environment will assist in moving this project to the development stage,” Pacifico said.
A phase two drilling campaign has been planned for April, and detailed technical studies will assess the opportunity to incorporate modern mineral processing technology into the project’s flowsheet to reduce capital and operating costs.
At midday, shares in Pacifico Minerals were up 25% to $0.005.