Millennial Lithium Corp. reported that bench scale process test work completed by SGS Canada Inc. (SGS) in their facilities in Lakefield, on brine from the Company's Pastos Grandes project in Salta, Argentina, has yielded battery grade (> 99.5% Li2CO3) lithium carbonate. Final purification testwork results yielded a lithium carbonate product that is 99.92% Li2CO3 with low levels of magnesium (Mg), calcium (Ca), boron (B), sulphate (SO4) and iron (Fe), with no other detectable metals. SGS has completed bench scale process trials on lithium-bearing brine from pumping well PGPW17-4 at Pastos Grandes. Approximately 600 litres of brine were shipped to SGS in Lakefield, Ontario for testing to investigate the amenability of the brine to producing battery grade lithium carbonate. SGS subjected the brine to liming followed by mechanical evaporation over several weeks and further removal of Ca and Mg via selective precipitation through the introduction of soda ash and caustic soda. Further evaporation reduced the volume to approximately 10 litres grading about 1.9 % Li. Standard and industry-tested purification procedures were employed on the concentrated brine including solvent extraction to reduce the boron content, followed by ion exchange to remove any remaining B. Ion exchange was followed by the main stage of carbonation with soda ash to produce a preliminary lithium carbonate product. The lithium carbonate product was then directed to further purification via bicarbonation with CO2. The final lithium carbonate product after the bicarbonation/decomposition process has a purity of 99.92% Li2CO3. Recovery of lithium through the primary lithium carbonate process was approximately 75% from the B-free solution and recovery through the bicarbonation/decomposition stage was approximately 74% of the lithium carbonate treated, however lithium losses are generally minimal in the process overall, as the lithium remaining in the mother liquor solution is typically recycled. In addition to the promising purity of the lithium carbonate produced, it is also encouraging that metals and other impurities, some of which can affect the quality and effectiveness of the lithium carbonate for battery performance, are very low to not detectable. Testing will continue at SGS to optimize the process, reduce impurities and improve recoveries and any positive achievements will be incorporated into the pilot plant design and tested on site at Pastos Grandes. Sampling was conducted in accordance with CIM guidelines for brine resource evaluation, with an appropriate chain of custody and QA/QC program in place for ensuring veracity, accuracy and precision of the analytical results.