Resource World Magazine

24 www.resourceworld.com F E B R U A R Y / M A R C H 2 0 1 5 rare earth eleMents (REEs) are special metals that are seeing increased use in high-tech machinery and electronics. Applications include specialty magnets, auto catalysts, fluid cracking catalysts, and phosphors, which are phosphorescent materials used in a variety of flat screens and devices. Chris Grove, President and director of commerce resources corp. [CCE-TSXV; CMRZF-OTC; D7H-FSE], a Vancouver-based exploration and development company, says the world is only beginning to realize the potential of REEs. "There should be many new applications and designs com- ing down the pike," said Grove. "More and more manufacturers and designers are looking to build new products that use the attributes of the whole range of REEs." Although REEs are plentiful, economic deposits are rare. In addition, separating the 17 REEs from each other and the host minerals can be a challenge. "Processing is the key to unlocking the commercial potential of REEs," said Grove. "That is what many projects and labs have been working on for a long time. But nothing new has been commercialized yet." According to the US Environmental Protection Agency (EPA), the two major mineral sources of REEs are bastnasite and monazite. Other minerals, such as xeno- time, apatite, yttrofluorite, cerite, and gadolinite, are also hosts. The last four minerals on the list have never been pro- cessed commercially, however. Processing REEs into usable products is a complex, trial-and-error process and varies from deposit to deposit. The EPA says there are a number of factors that affect the selec- tion of the most effective treatment process. They include the type and complexity of the deposit; the type and nature of other valuable minerals that are present with the REEs; the type and composition of the individual REE minerals; and the social and environmental acceptability of the process. There are a number of primary steps in processing REEs, says Darren Smith, a spokesman for Edmonton-based Dahrouge Geological Consulting Ltd., which discov- ered Commerce's Ashram REE deposit in northern Québec in 2009. They are the liberation and concentration of the REE minerals from the host material, dissolu- tion of the mineral concentrate in acidic or alkaline solutions; separation of the REEs using solvent extraction or ion exchange; and reduction of the individual REEs into pure metals. Smith says the first step typically includes crushing the ore and separating the REE by flotation, magnetic, or gravity separation; this increases the percentage of REEs in the working material by creating a mineral concentrate. Later in the process, thermal and chemical reactions convert the mineral concentrate's REEs into a soluble form. Hydrometallurgical techniques that include leaching, extraction, and pre- cipitation are used to bulk precipitate the REEs and further process them into sepa- rated oxides. Additional processing may refine the oxides into high-purity metals. Smith says Commerce is one of only two or three REE companies in development that has successfully created a mineral concentrate of more than 40% total rare earth oxides at more than 70% recovery. "All major producing REE deposits, apart from the South China clays, produce a minimum 30% mineral concentrate for downstream processing," he said. Grove says Orbite aluminae Inc. [ORT- TSX; EORBF-OTCQX] is working on a new processing technology. According to Orbite, the process not only extracts alu- mina from aluminous clay, but also has the potential to extract high-value ele- ments and rare earths. The Orbite process of producing metallurgical-grade alumina involves crushing and then acid-leaching the aluminous clay stone found at the com- pany's Grande-Vallée property in eastern Québec. Then, by varying the temperature and acidity of the solution, the process isolates the aluminum component and removes iron and other impurities. Grove says there are deposits of REEs almost everywhere in the world, but China has until now been the largest single sup- plier of feed stock, controlling about 95% of world REE production. "China's impor- tance as the single largest producer is still current, but their assets are impacted by several factors," said Grove. "For example, they are generally considered – by the Chinese themselves and by anyone else in the world who has visited these sites – to be significant polluters." Grove says China cannot continue REE production at the same rate of extraction forever. "As a result, the Chinese are actively looking for foreign suppliers of feed stock, especially heavy REE deposits hosted in xenotime," he said. Despite China's size and importance, it is not a single monolithic rare earth elements demand up for high-tech applications by Peter Caulfield A flotation test on material from the Ashram deposit on the Commerce Resources Eldor property. MINING

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