Commerce Resources Corp. Updates Metallurgical Test Work for its Ashram Rare Earth Element Deposit in Northern Quebec
VANCOUVER, Nov. 15, 2012 /PRNewswire/ - Commerce Resources Corp. (TSXv: CCE, FSE: D7H, OTCQX: CMRZF) (the "Company" or "Commerce") is pleased to provide an update on the ongoing metallurgical test work for the Company's 100%-owned Ashram Rare Earth Element ("REE") Deposit located in northern Quebec. Significant metallurgical advancements have been made over those detailed in the project's Preliminary Economic Assessment ("PEA") as released on May 24, 2012.
Initial Cracking Tests
Cracking of mineral concentrates began in June, 2012 at Hazen Research Inc. ("Hazen"), Colorado where initial tests focused on determining acid consumptions and demonstrating the cracking process outlined in the Company's PEA. This process involves known and conventional techniques common to the simple rare earth mineralogy of Ashram (monazite, bastnaesite, and xenotime), in which the mineral concentrate is dissolved in sulphuric acid. This facilitates the removal of impurities (Th, Fe, Mg, Ca, F, etc.) and ends with the precipitation of REE's as a mixed pure oxide or carbonate product.
Preliminary results are available on low- to mid-grade concentrates (~6-12% Total Rare Earth Oxide, "TREO"), while larger volumes of high-grade concentrates are being produced for the ongoing test work. To date, results have shown that the rare earths are readily entering solution with some loss indicated into the residual gypsum (solid) as expected. In only the first few bench scale tests, recoveries into solution, from the mineral concentrates, have totalled up to 98% for a single REE (La) with an average of 94% TREEs (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu + Y). As anticipated, recoveries are highest for the LREEs (La, Ce, Pr, and Nd). Test work is being completed to liberate the remaining REE's present within the residual products, with the goal of bringing recoveries into solution of essentially 95%+ for the light, middle, and heavy REEs.
Impurity removal is underway and progressing as anticipated. Most fluorine is removed from the system as HF gas during initial sulphuric acid attack. The HF is then condensed and captured. The process is being evaluated for its potential to convert the HF into an acid-grade fluorspar or a hydrofluoric acid by-product. It should be noted that the economics of any potential by-product(s) were not evaluated by the recently completed PEA for the Ashram Deposit.
Advancements in Flotation Grade and Recovery Rates
The PEA outlined a base case mineral concentrate grade of 10% TREO at a recovery rate of 70%. Of the new test results, highlights include an 11.2% TREO mineral concentrate at a 76% recovery (XRF) representing TREO upgrading of 6.8 times. In addition, recoveries of over 75% have been achieved while maintaining significant mineral concentrate grades. Most importantly the near term goal, as outlined in the PEA, of creating a 20% TREO mineral concentrate with >60% recovery has been achieved with test 3560-148 returning 20.1% TREO at a recovery of 65%. This result was achieved via a fine grain size screening technique at the bench scale. The viability of screening at this grain size on a larger scale is being assessed. Select test results are detailed in the following table:
Test Results of Mineral Concentrate Upgrading via Conventional Flotation
Percent of Original
|PEA BASE CASE||10.0%||70%||5.1 times|
Portable Niton XRF Analysis
Niton XRF Analysis(3)
(Ce2O3 + La2O3, + Pr2O3 + Nd2O3)
|PEA BASE CASE||-||10.0%||70%||5.2 times|
|(1)||ICP analysis is quantitative with TREO defined as Ce2O3 + La2O3 + Pr2O3 + Nd2O3 + Eu2O3 + Sm2O3 + Gd2O3 + Tb2O3 + Dy2O3 + Ho2O3 + Er2O3 + Tm2O3 + Yb2O3 and + Y2O3. Lu2O3 is not included in the summation.|
|(2)||Based on an average 1.95% TREO starting head grade.|
|(3)||Niton Portable XRF analysis is semi-quantitative and expressed as a summation of Ce2O3, La2O3, Pr2O3, and Nd2O3 only. The XRF vs. ICP analytical methods have consistently shown to correlate well for Ce2O3, La2O3, Pr2O3, and Nd2O3 due to the fine grain size and homogenous character of the mineral concentrates, thereby allowing for a quick, economic, and effective means of characterizing a mineral concentrate. As the XRF data is semi-quantitative it is not as accurate as ICP data and it has been shown that XRF data for higher grade concentrates may give TREO values up ~10-15% higher than TREO values determined by ICP.|
|(4)||TREO is inferred from Hazen's summation of Ce2O3, La2O3, Pr2O3, and Nd2O3 with extrapolation, based on known distribution, used to determine the value for the remaining REOs. The extrapolation assumes recovery remains constant across all the REOs.|
|(5)||Test 3503-28 (ICP) is a repeat of test 3540-30 (XRF)|
As the identification of the best carbonate depressant and rare earth mineral collector is the focus of the current test work, it is important to note that the Ashram tests are not optimized.
The Ashram metallurgical flow-sheet is amenable to the industry preferred method of initial physical upgrading to a rare earth mineral concentrate in order to reduce downstream processing costs and optimize production parameters. The ability to first upgrade and produce a rare earth mineral concentrate is the most effective method of reducing acid consumption and associated costs during the required mineral cracking stages that follow. Conventional flotation is the physical upgrading process applied to the Ashram material whereby only minor amounts of reagent are needed to promote selective flotation of a much larger volume of rare earth material. This significantly reduces the volume of material to be processed downstream.
Two reagent schemes have been identified showing the greatest selectivity during the flotation process. In preparation for pilot plant level test work, these two schemes will be further optimized by evaluation of reagent ratios (each scheme uses a two collector reagent combination with one depressant). Once the optimal ratio is determined, other factors will be optimized such as temperature, pH, etc. with grade and recovery expected to improve. Further, test work will continue in parallel for other promising reagent combinations as many have yet to be evaluated. In addition, screening and sizing techniques are being evaluated that show promise for additional grade improvement and reduced grind time.
Ongoing Metallurgical Activities
In late summer 2012, a bulk sample of representative in-pit material (approximately 30-35 tonnes) was collected from the Ashram Deposit in preparation for pilot plant studies expected to commence in Q2/Q3 of 2013.
To date, scaling work on 10 kg batches, up from 200 g, have indicated the repeatability of results at a larger scale. Hazen will further demonstrate this at the bench scale and also evaluate the repeatability of results at an even larger and more continuous scale in pilot plant test work scheduled for the Q2/Q3 2013.
Darren L. Smith, M.Sc., P.Geol., Dahrouge Geological Consulting Ltd., a qualified person as defined by National Instrument 43-101, supervised the preparation of the technical information in this news release.
Eric Larochelle, Eng, and Alain Dorval, Eng., Manager- Process, Mining and Mineral Processing., of Roche Ltd, Consulting Group, Qualified Persons as defined by National Instrument 43-101, reviewed the technical information presented in this news release.
About Commerce Resources Corp.
Commerce Resources Corp. is an exploration and development company with a particular focus on rare metal and rare earth element deposits with the potential for economic grades and large tonnages. The Company is focused on the development of its Upper Fir Tantalum and Niobium Deposit in British Columbia and the Ashram Rare Earth Element Deposit in northern Quebec.
On Behalf of the Board of Directors
COMMERCE RESOURCES CORP.
President and Director
Neither TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.
This news release contains forward-looking information which are subject to a variety of risks and uncertainties and other factors that could cause actual events or results to differ from those projected in the forward-looking statements. Forward looking statements in this press release include our projected timeline and consultants for the PFS, the focus of our metallurgical work, our planned drilling program, that the Ashram deposit can be developed economically as an open-pit mine; all information contained in the pre-feasibility study; and that we can build shareholder value through the discovery and development of Canadian rare metal and rare earth element deposits. These forward-looking statements are based on the opinions and estimates of management and its consultants at the date the information is disseminated. They are subject to a variety of risks and uncertainties and other factors that could cause actual events or results to differ materially from those projected in the forward-looking information. Risks that could change or prevent these statements from coming to fruition include changing costs for mining and processing; changing forecasts of mine production rates; the timing and content of upcoming work programs; geological interpretations based on drilling that may change with more detailed information; potential process methods and mineral recoveries assumption based on limited test work; the availability of labour, equipment and markets for the products produced; market pricing for the products produced; and despite the current expected viability of the project, conditions changing such that the minerals on our property cannot be economically mined, or that the required permits to build and operate the envisaged mine can be obtained. The forward-looking information contained herein is given as of the date hereof and the Company assumes no responsibility to update or revise such information to reflect new events or circumstances, except as required by law.
SOURCE Commerce Resources Corp.