Plateau Energy Metals Inc. announced it has completed a preliminary test work program (“Program”) for the recovery of potential by-products such as sulfate of potash (“SOP”), caesium and rubidium from its Falchani Lithium Project in Peru. This Program was conducted by ANSTO Minerals, based in Sydney, Australia. Highlights of the Program: The final test work was run on a sample of Falchani lithium-rich tuff material at the same conditions as the lithium leaching studies published by the Company in the PEA with concentrations of 3,400 ppm lithium; 3 wt% K; 600 ppm Cs and 1,400 ppm Rb; Extractions of the following metals (from lithium-rich tuff into sulfate solution via previous test work and supported in this Program): Potassium (“K”): 43%, Caesium (“Cs”): 84%, Rubidium (“Rb”): 67%.Excellent rejection of aluminum using ‘simple’ neutralization with lime or high temperature treatment (calcination); Caesium precipitation: selective crystallization of >99% of the Cs and Rb from PLS, along with some K, by cooling to between 20 and 30°C following the PEA flowsheet; and Precipitation of approximately 18% of K from leaching of feed material through to PLS at temperatures below 20°C to a purified K-alum in the first pass, with future test work potentially optimizing the yield. Program Details: This Program was an extension of ANSTO’s previous test work to support the Falchani Project National Instrument 43-101 PEA technical report titled “Falchani Lithium Project NI 43-101 Technical Report – Preliminary Economic Assessment” prepared by DRA Pacific, effective February 4, 2020 (filed on SEDAR March 20, 2020), in which a mixed alkali metal alum is crystallized from the PLS prior to purification (refer to flowsheet linked above). This mixed alkali metal alum is where >99% of Cs and Rb report to in the process, which forms a potential feed for further processing to realize the value of the contained caesium. Three different processing options were examined in the Program, including: Neutralization /Sulfate Crystallization (“Neutralization Option”); Calcination /Water Leaching /Sulfate Crystallization (“Calcination Option”); and Upgrading of the Mixed K/Rb/Cs-alum (“Pre-Concentration”). The results of the Program have demonstrated excellent rejection of aluminum, iron, and other trace elements, and substantial recoveries of the alkali metals (potassium, rubidium and caesium) using either an initial treatment of calcination at between 700 to 800oC in the Calcination Option, or dissolution of alum followed by neutralization using lime in the Neutralization Option. The test work also demonstrated selective crystallization of >99% of the Cs and Rb, in both the Neutralization Option and Calcination Option from actual PLS by cooling to between 20 to 30°C. At this point the Rb and Cs content is reduced to below detection limits (1 mg/L). A proportion of potassium also crystalizes in this step. At temperatures below 20°C a portion of the K available in solution precipitated out while lithium and other metals, remained in the sulfate solution. This resulted in an unoptimized first pass recovery of approximately 18% of the K in solution and ANSTO believes future test work may further improve the yield. As described in the PEA flowsheet, the lithium-rich solution continues with an additional three-stage conventional impurity removal prior to the next steps utilized to precipitate a low impurity, battery quality lithium carbonate.