Core Lithium Ltd. announced the production of battery grade lithium hydroxide monohydrate (LH) from spodumene mineral concentrate from the Finniss Lithium Project. The scoping level test work program has demonstrated that the conventional `direct' flowsheet can be applied to the processing of the mineral concentrate sample to produce battery grade lithium hydroxide monohydrate. In light of the success of this program and the recently granted Federal Government Major Projects status, Core is now considering the obvious down-stream value potential given the Project's synergies with the adjacent Middle-Arm industrial infrastructure near Darwin. As well as the alignment with Australia's Modern Manufacturing strategy, and the rapid expansion of global lithium battery supply chains to meet the demands of the ever-increasing LIB, electric vehicle (EV) and renewable energy markets. Demonstration of the production of battery grade LH in this program provides Core and its customers confidence in the value of the Finniss Project, its importance to Australia's northern regional economy, and strengthening Australia's position further downstream in the global lithium battery supply chain. Core remains focussed on completing the Finniss Lithium Project concentrate DFS and finalising current live off-take negotiations ahead of reaching a Final Investment Decision (FID) in third quarter of 2021. Testwork Program: Objectives: The test work program was completed by the Minerals Business Unit of the Australian Nuclear Science and Technology Organisation (ANSTO). ANSTO is one of Australia's public research organizations and its Minerals personnel have extensive lithium processing experience with hard rock and brine feedstocks, to produce high purity chemical concentrates required for the manufacture of lithium ion batteries (LIBs). The main objective of the test work program was to demonstrate the production of `battery grade' LH using a sample of the Finniss Project spodumene mineral concentrate composited from previous Grants and BP33 gravity concentrate test work. Scoping level test: work was conducted on the major unit processes of the `direct' conversion approach. The `direct' conversion flowsheet involves decrepitation, sulfation baking /water leaching, purification, Glauber salt crystallisation and lithium hydroxide crystallisations. The test work program was specifically designed to confirm the suitability of the major unit processes and provide an increased level of confidence in the process modelling. Results: Without optimisation of the decrepitation, sulfation baking or water leaching conditions, excellent extraction of lithium (>95%) was achieved in two separate tests on 2 kg samples of blended concentrate. Conventional impurity removal steps as well as three stages of crystallisation afforded excellent rejection of the key impurities, potassium, sodium and sulphur as well as minor impurities such as rubidium and caesium. Conclusions: The most critical factor to the successful extraction of lithium from spodumene mineral concentrates is the decrepitation step and the complete conversion of – to -spodumene. This has been achieved for the samples of the initial Finniss spodumene mineral concentrate, with additional mineralogical data increasing confidence in the processibility of the mineral concentrate. Following decrepitation to -spodumene, the major unit processes of a conventional `direct' process flowsheet can be applied to convert the contained lithium to lithium hydroxide monohydrate, which satisfies the commonly referenced Livent battery grade LH specification. The knowledge of the process chemistry associated with all the major unit processes, especially each stage of LH crystallisation, gained from this program has allowed development of a preliminary process model.