Sheffield Resources has revealed potential to extend mining of the higher grade ore at its Thunderbird mineral sands project in Western Australia after registering a 10 per cent reserve jump.
The company has reported a 500,000 tonne increase in contained zircon to a 6.4 million tonne ore reserve, underlining “the significant scale” of the Thunderbird deposit.
Sheffield will mine the “exceptionally” high grade ore of 1.02 per cent in the proved category, in support of its recent decision to focus on increasing zircon output.
The period of mining the higher grade ore has been extended from seven to 10 years.
Sheffield expects to release an updated bankable feasibility study (BFS) based on the updated reserve in the coming weeks.
“In summary, the BFS update targets an increase in zircon production by focusing on higher grade zircon ore and a 38 per cent increase to the ore mining rate,” Sheffield managing director Bruce McFadzean said.
“The feed rate to the wet concentration plant has been lifted from 788 dry tonnes per hour (2017 BFS) to 1085 dry tonnes per hour. This will apply to both stage one from year one and stage two from year five onward.”
Sheffield’s BFS shows Thunderbird is a technically low risk project with significant levels of production over a long mine life of 37 years.
The company is targeting initial production in 2021, with a production profile aligned with the emerging supply deficit in global zircon markets.
Sheffield has identified China, India and Europe as its key regional markets for its premium grade zircon, and the Chinese concentrate processing market for its zircon concentrate.
The company plans on supplying an average of 67,000 tonnes a year of premium zircon in years two to four, increasing to an average of 120,000 tonnes a year for the next six years and an average of 90,000 tonnes a year from year 11 onwards.