Tambanis now holds circa 3.2 million shares, with several lines of options and rights.
Earlier in the month, chairman, Stephen Copulos, purchased 1 million shares on market.
Black Rock has been rapidly advancing its graphite assets in Tanzania.
The company's Mahenge project now hosts the third largest JORC graphite resource in Africa - and the fourth largest in the world.
It's not always the size of the resource that's important, but the quality, which Mahenge has.
Mahenge offers significant flexibility for potential development into a long life (+30 year) mining operation.
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