Plateau Uranium reports 'Proof of Concept' Test work results highlighting recovery of both Lithium and Uranium into separate individual Concentrates
The Company is continuing additional test work on uranium, lithium and other associated metals with the intention of further optimizing the process and establishing capital and operating costs for uranium and lithium co-production from the Macusani deposits.
Highlights
- The new test work commenced in April 2017 on representative bulk samples collected from two mineralized horizons from separate uranium deposits considered in the Company's PEA: a sample representative of average U-Li grades from planned open pit material (SOC) as well as a high grade uranium sample typical of potential underground material (PCH).
- The average U-Li SOC sample contains 579 ppm U and 402 ppm Li and the high uranium PCH sample contains 5906 ppm U and 577 ppm Li.
- Both samples exhibited similar metallurgical response indicating that both mineralization types could be upgraded employing a single flowsheet (see Figure 1 - Simple Concentration Flow Sheet).
- All results given below are non-optimized.
- The mineralization responds to a simple crush followed by attritioning and screening steps. Using standard metallurgical processing steps, the uranium-bearing mineral, autunite can be separated as a coarse fraction and leached in a weak sulfuric acid for recovery to an ion exchange resin. The fine fraction is amenable to magnetic separation resulting in a lithium-rich concentrate and some of the uranium in the fine fraction co-reports with the lithium in the magnetic fraction.
- Initial attrition-screen results are suggesting that in excess of 80 % of the uranium can be recovered in the plus 1 mm and sub 3.3 mm screen fraction. Leach tests have shown rapid uranium recoveries exceed 95% in a weak sulfuric acid tank leach scenario.
- Magnetic separation results indicate that approximately 47% of the lithium present in the PCH sample can be recovered to a magnetic concentrate comprising only 17% of the original mass. Approximately 5% of the uranium reports to this lithium-rich magnetic fraction.
- Lithium Grades (measured as Li) reported in the magnetic concentrates, were in the 1800-2000 ppm range or 9,500 -10,500 ppm Li Carbonate equivalent.
- Uranium grades in the attrition-screen gravity concentrates range from 2,000 ppm to >8,000 ppm U.
- Test work on the base case Lithium recovery route via whole ROM leaching continues to go well in Lima, Peru and will be reported separately when this work is concluded.
- Uranium and lithium co-production at Macusani represents significant potential value with commodity consensus prices for the mid to long term (beyond 2020) forecasted to range between US$53-75/lb U3O8 and US$8000-10,000 for Lithium Carbonate according to CIBC Global Mining Group Analyst Consensus research published September 29, 2017.
Ted O'Connor, CEO of Plateau Uranium commented: "These latest results further highlight the economic opportunity for enhancing our already robust Uranium Project with a potential Lithium by-product.
The low mass pull reported above on the separate magnetic, Li-rich concentrate and the Uranium-rich concentrate may allow the Company to reduce the Capex associated with the downstream recovery flow-sheet, reduce the size and footprint of the processing operation, as well as improving overall production recoveries of the proposed Lithium Carbonate and U3O8 products.
Magnetic separation and Gravity concentration are simple, well established process options with low operating cost potential. We believe that the potential value from lithium co-production represents a significant economic driver for the Macusani project. To this end, the next phase of test work will be focused on establishing more detail on the Capital and Operation cost numbers to quantify the potential value-added impact of uranium and lithium co-production to a PEA/PFS level."
Details
This current phase of work was conducted at SGS in Perth in Q2-3/2017 and commenced with a test flowsheet employing a crush-wet scrub-screen flowsheet. The screen fraction below 1 mm and above 45 micron was then subjected to a magnetic separation step.
It soon became apparent that excessive size reduction was occurring in the wet scrub step to the extent that this was replaced with an attritioning unit. The attritioning unit reduced the mass fraction of the sub 45 micron fines where a disproportionate mass of the Lithium and Uranium were reporting.
The attritioning step was found to leave much of the uranium-bearing mineral, autunite in the coarser fractions where a straight forward sulphuric acid tank leach process similar to that employed in the Namibian acid leach operations has been considered.
The sub 1 mm and plus 45 micron fraction from the screening circuit was found to be ideal for presentation to a high intensity magnetic separation. The biotite, in which lithium was present, reports to the magnetic accept fraction.
Developmental work is ongoing and there is scope for further Lithium and Uranium recovery improvements.
Qualified Persons
Mr. Grenvil Dunn, Pr Eng (RSA), C Eng (UK), FIChE, MSAIMM, MSAIChE of Hydromet Pty Ltd, a consultant to the Company, is a Qualified Person as defined under National Instrument 43-101 Standards of Disclosure for Mineral Projects, and has reviewed and approved the scientific and technical information contained in this release.
About Hydromet Pty Ltd
Hydromet Pty Limited is an international consulting company for the metals and mining industry. The company is based in South Africa and was established in 2000 by its director Grenvil Dunn. Mr Dunn is a Chemical Engineer with over 45 years of experience, particularly in mineral processing, flow sheet design and development with direct experience in uranium and lithium.
About Plateau Uranium
Plateau Uranium Inc. is a Canadian uranium-lithium exploration and development company focused on its properties on the Macusani Plateau in southeastern Peru. The Company controls all reported uranium resources known in Peru, significant and growing lithium resources and mineral concessions covering over 91,000 hectares (910 km2) situated near significant infrastructure. Plateau Uranium is listed on the TSX Venture Exchange under the symbol 'PLU', quoted on OTCQB under the symbol "PLUUF" and on the Frankfurt Exchange under the symbol 'QG1'. The Company has 58,043,354 shares outstanding.
Forward Looking Information
This news release includes certain forward-looking statements concerning possible expected results of exploration and future exploration activities. Forward-looking statements are frequently identified by such words as "may", "will", "plan", "expect", "anticipate", "estimate", "intend" and similar words referring to future events and results. Forward-looking statements are based on the current opinions and expectations of management. All forward-looking information is inherently uncertain and subject to a variety of assumptions, risks and uncertainties, including risks and uncertainties relating to the interpretation of drill results, the geology, grade and continuity of mineral deposits; the possibility that any future exploration, development or mining results will not be consistent with our expectations; mining and development risks, including risks related to accidents, equipment breakdowns, labour disputes (including work stoppages and strikes) or other unanticipated difficulties with or interruptions in exploration and development; the potential for delays in exploration or development activities; risks related to commodity price and foreign exchange rate fluctuations; risks related to foreign operations; the cyclical nature of the industry in which we operate; risks related to failure to obtain adequate financing on a timely basis and on acceptable terms or delays in obtaining governmental approvals; risks related to environmental regulation and liability; political and regulatory risks associated with mining and exploration; risks related to the certainty of title to our properties; risks related to the uncertain global economic environment; and other risks and uncertainties related to our prospects, properties and business strategy, as described in more detail in Plateau Uranium's recent securities filings available at www.sedar.com. Actual events or results may differ materially from those projected in the forward-looking statements and Plateau Uranium cautions against placing undue reliance thereon. Neither Plateau Uranium nor its management assume any obligation to revise or update these forward-looking statements.
For more information please visit www.plateauuranium.com.
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Contact
Plateau Uranium Inc.
Ted O'Connor
CEO
+1-416-628-9600
ted@plateauuranium.com
Website: www.plateauuranium.com
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