Swiss mining giant Glencore has commenced hoisting operations at its Ernest Henry copper-gold mining project near Cloncurry in north-west Queensland, Australia. This marks the mine's transition from an open pit operation to an underground unit.
As part of its transition, the company has invested $589m to hoist a kilometre-deep shaft that started operating at the mine.
Glencore North Queensland copper assets CEO Mike Westerman said Ernest Henry's development strengthens the production profile and sustainability of the company's regional copper operations.
"Our assets in Mount Isa and at Ernest Henry accounted for around 14% of Glencore's global copper production in 2013," Westerman said.
"This investment in Ernest Henry has effectively added 14 years to the life of the mine to 2026. We're pleased to have this opportunity to sustain production at a higher rate, continue to support around 500 employees plus contractors and deliver on-going benefits to the Cloncurry community and economy."
The Ernest Henry project is expected to produce around three to six million tonnes of copper a year in 2015.
In addition to this, the operations will double the annual metal production to 50,000t of copper and 70,000oz of gold until its extended lifetime.
The latest milestone follows the transition efforts started by Glencore in December 2009, when it dug more than 50km underground, installed underground primary crusher and conveyors, as well as a 75m permanent headframe, and reconfigured the concentrator to align with underground production rate.
The company is currently using a sub-level caving mining method to carry-out operations at four levels of the mine.
Ernest Henry had total ore reserves of 74 million tonnes at 1.04% copper and 0.53g per tonne of gold at the end of December 2013.
Image: Glencore is using a sub-level caving mining method for its Ernest Henry copper and gold mine project. Photo: courtesy of Glencore.