Blackstone Minerals Limited provided an update on its ongoing metallurgical test work programmes for both the Ta Khoa Nickel Project and the Ta Khoa Refinery Project during their respective Definitive Feasibility Study phases. Ta Khoa Refinery Project: In October 2021, Blackstone announced the appointment of Tier 1 engineering, minerals processing and metallurgical consultants Wood and ALS to perform critical roles in the delivery of the TKR DFS. With the support of Wood's expertise in hydrometallurgical flowsheet development and ALS' expertise in metallurgical laboratory testing and continuous integrated flowsheet piloting, Blackstone announced the following test work updates: Completion of bench test work program: The hydrometallurgical bench test work program successfully confirmed the improved DFS process flowsheet.

The data collected during the bench test work program has been used to update the TKR plant design criteria; Design, procurement, and assembly of piloting equipment: Extensive work has been completed between Blackstone, Wood and ALS to develop a pilot campaign that is fit for purpose and aligns with the DFS flowsheet; Successful commissioning of piloting equipment: ALS has successfully assembled the TKR flowsheet and commissioned all unit operations from mixed hydroxide precipitate re-leach through to the production of battery grade metal sulphates. The pressure oxidation leach flowsheet will be commissioned by end of August 2022; Successful operation of MHP to metal sulphate from third party MHP: Blackstone has successfully piloted the TKR flowsheet, confirming company's ability to process third-party MHP to battery grade metal sulphates. The next steps for the TKR piloting program will be to pilot nickel concentrate feed (sourced from the mine site and third-party nickel sources) to produce MHP, then convert MHP to battery grade metal sulphate in preparation for precursor cathode active material processing.

Ta Khoa Nickel Project: In May 2022, Blackstone announced the appointment of process engineering, design, and construction company GR Engineering ("GRES") as the consultant for the upstream concentrator and non-process infrastructure, and collation of the TKN DFS.