A detailed scoping study for the production of a sulphuric acid bi-product from Broken Hill Prospecting’s world-class Broken Hill Cobalt Project in the far west of New South Wales has highlighted significant potential for a long-term operation with a low capital start-up and staged development. The study enhances project flexibility for development of a cobalt operation.
The study confirmed that pyrite from the company’s Pyrite Hill, Big Hill and Railway cobalt deposits could yield valuable sulphuric acid bi-product. Currently sulphuric acid is in strong demand in fertilizer production, mineral processing and other industries. Pyrite treatment would also provide significant cobalt and iron recovery.
Five fast-track, low-cost development options have been identified in the study at nominal annual processing rates of 1.5 million to 7.5 million tonnes. All of the known cobaltiferous pyrite mineralization is located near-surface within an exploration licence and two mining leases, and can be mined by open cut methods.
Broken Hill Prospecting’s managing director Ian Pringle says, “This first step towards development of the cobalt project is important because it shows that production of pyrite to produce sulphuric acid could be a valuable revenue stream to support cobalt sales. This outcome gives us tremendous flexibility in developing this large project, including how mining should be undertaken and what the end product should be.
“Next we need to undertake resource definition, metallurgical studies, mine planning, infrastructure and transport needs, and also evaluate the best marketing approach. These project studies will be invaluable in determining how to deliver the best value,” he adds.
A recent resource evaluation estimated the combined inferred resources of the three deposits as 35.7 million tonnes of pyrite mineralization with an average grade of 1.85 pounds/tonne of cobalt. In addition, ‘potential’ for between 37 million and 59 million tonnes of pyrite mineralization of similar cobalt grade was estimated.
Broken Hill Prospecting is a mining and exploration company seeking to develop significant cobalt deposits near Thackaringa, 25km southwest of the world famous mining centre of Broken Hill. The deposits are geologically unusual because they do not occur as a bi-product with richer copper or nickel deposits, as is the case in nearly every other mine around the globe. Cobalt, therefore, would be the main focus of any mining development.
The deposits exist near surface and recent drilling has defined a footprint which is at least 4km in length that is open at width, depth and length. The mineralization can be simply processed to a cobalt-pyrite concentrate, which, because of the excellent location, could be transported by rail/road/sea for processing to produce cobalt, sulphuric acid and iron ore products.