Mica Offtake Offers An Attractive Bonus
Big River Gold Ltd (ASX:BRV) reports that a significant stage of the analysis being undertaken to assess the commercial viability of mica production at the company’s 100% owned Borborema Gold project, has been completed by Nagrom in Perth, Western Australia.
The programme currently being undertaken by Nagrom follows on from the testwork completed successfully by Dorfner Analysenzentrum und Anlagenplanung Gmbh (ANZAPLAN) in Germany.
Executive Chairman, Andrew Richards, said the aim of Nagrom’s work is to produce a commercially viable bulk concentrate in the first instance of which details of the chemical and physical properties can be made available to potential distributers or other offtake counterparties.
Mr Richards said the Borborema ore body contains very significant quantities of auriferous mica that will be processed through its planned 2Mtpa CIP process plant. Initial work showed that after processing through the milling, cyanide leach and elution circuits, a substantial amount of mica could be readily separated by magnetic separation.
This product retained attractive commercial chemical and physical properties including flake size and importantly, being free of deleterious crystalline silica (quartz).
Magnetic separation represents a technically simple, low cost and chemical free process that could be readily included or retro-fitted to the currently designed gold plant to process the dry tails.
The mica market is specialised and relatively small requiring careful management to establish offtake without disrupting the market. However, Borborema does offer the market good quality product derived from ethical mining practices not always present in this sector4. In conjunction with supplying samples to prospective customers, Big River will carry out a market study aimed at identifying markets for the product within Brazil and internationally. Mr Richards said that with the Borborema Project already considered to be a robust and standalone gold project, Big River believes that the testwork results warrant follow up to unlock the potential of mica sales as a by- product. If this proves viable, the company anticipates it will have a significant positive impact on the economics of the already very attractive Borborema Gold Project and gold production costs.