Extended test work on samples taken from two manganese deposits in the East Pilbara region of Western Australia have suggested two production streams for Black Canyon (ASX:BCA), instead of the initial plan for one.
Black Canyon rolled out heavy liquid separation (HLS) testing across two samples taken from five holes at the KR1 and KR2 deposits in late 2023, with each hole going down to 10 metres.
Both samples were notable for high grades of manganese concentrates, measuring between 30.2 and 37.4 percent from KR1 and between 29.2 and 35.3 percent from KR2.
Black Canyon’s initial plan was to produce high purity manganese sulphate monohydrate (HPMSM) feedstock from the two deposits at a target grade of between 30 and 33 percent.
However, since several results from this testing go well beyond such grades, this opens another potential pathway for the company: production of a smaller volume, but higher-grade manganese product – at around 35 to 37 percent – in addition to the lower-grade feedstock.
Both deposits are located within the Balfour Manganese Field, for which Black Canyon has achieved a maiden mineral resource estimate of 103 million tonnes (Mt) at 10.4 percent manganese containing 10.7 Mt of manganese based on an extensive program of reverse circulation drilling.
More specifically, KR1 carries an indicated resource estimate of 79 Mt at 10.0 percent manganese, while KR2’s resource estimate is inferred at 24 Mt at 11.9 percent manganese.
Executive director Brendan Cummins said the results had provided stronger guidance for where Black Canyon might go with its manganese portfolio.
“The Company continues to deliver on its strategy of discovering substantial mineral resources that can be developed to produce manganese concentrates for alloying used in the steel industry and downstream HPMSM processing,” he said.
“The primary purpose of this current beneficiation testwork is to produce 100 to 150 kilograms of manganese concentrate from KR1 and KR2 samples that can be used for further detailed hydrometallurgical testwork as we seek to optimise and refine the HPMSM flowsheet.
“The metallurgical results are significant for two reasons. Firstly, we have achieved a higher grade manganese concentrate above our target range of 30 – 33 percent manganese and secondly it improves our understanding of the relationship between concentrate grade, recovery and particle size liberation.”
Some might say now is a good time to be setting up production for a manganese deposit in Australia, given recent news that South32 will be temporarily suspending its Groote Eylandt Mining Company (GEMCO) operations in the Northern Territory, due to damage caused by tropical cyclone Megan.
Black Canyon is trading at 10c.