Sep. 9, 2019 - Tanzanian graphite developer Black Rock Mining Limited (BKT: ASX) (“Black Rock” or the “Company”) is pleased to announce it has completed a large-scale spheronising and purification trial using 400kg of sub 80 mesh concentrate generated during the March 2019 Pilot Plant run. 

Highlights:

• Spheronising yields of up to 53% achieved, significantly exceed industry standard for battery anode materials
• 99.98% TGC* purity delivered with simple acid leaching, exceeding industry standard for battery anode
materials
• Large scale Spherical Purified Graphite (SPG) production trial of 400kg is 100 times larger than Black Rock’s
previous laboratory experiments
• Proposed Mahenge concentrator flowsheet demonstrated no damage to flake
• Chinese industrial trial replicated strong results previously achieved in Western laboratories

The trial has demonstrated a yield to final product of 48% and 53%, and final purity of 99.98% TGC* using commercial scale equipment in commercial processing and in dedicated research facilities. These outcomes significantly exceed Chinese Industry Benchmark yields of 35-45% and purity of 99.95% while using standard equipment and techniques. Spherical Purified Graphite (SPG) produced from the trials has been sent to interested parties for further testing.

Commenting on the spheronising results, Black Rock’s CEO, John de Vries, said

“The best way to think of the bulk spheronising trial is that it is the equivalent of our pilot plant strategy, but in this case, done downstream. The fundamental objectives of the pilot plant approach remain the same and that is to improve our attractiveness to financiers and investors by demonstrating and de-risking Mahenge’s superior performance in our potential customers’ business.

In completing this round of work, we had two key objectives. Firstly, to ensure that the flow sheet developed for the Mahenge concentrator preserves the integrity of the flake and does not impair spheronising performance. Secondly, to demonstrate that offtake partners can achieve industry leading performance using our flake in their existing facilities. This underpins our price point and volumes in our pricing framework agreements.

Conducting a large-scale spheronising trial using industry standard equipment allows us to assess how initial laboratory results obtained during the Pre-Feasibility Study in 2017 (refer to ASX release 7 June 2017) scale up in the industrial context that our customers operate in. For our customers to be able to replicate the best-in-class spheronising results, that are up to a 50% improvement on current yields, while able to replicate results obtained in highly controlled laboratory conditions by skilled researchers, with no modifications to their processes, is simply stunning.

Concentrate used for these trials was produced at the Chinese pilot plant where the design flowsheet intended for the Mahenge Graphite Project was demonstrated. The exceptionalspheronising yields obtained in the trial show that the planned flowsheet does not damage our flake. This talks to the unique geological advantage of Mahenge graphite, and the diligence applied to design and trials to optimise and de-risk our flowsheet before construction.

With the completion of this technical work, we can confidently focus on completing our financing discussions and documenting the shareholder agreement with the Tanzanian Government.”