DEFENSE METALS (DEFN.V): PRE-PILOT HYDROMETALLURGY TESTING YIELDS 97.3% RARE EARTH ELEMENT EXTRACTION FROM WICHEEDA FLOTATION CONCENTRATE
News Release – Vancouver, British Columbia – February 16, 2021: Defense Metals Corp. (“Defense Metals”) (TSX-V:DEFN / OTCQB:DFMTF / FSE:35D) is pleased to announce that it has received additional pre-pilot hydrometallurgical test work utilizing high-grade rare earth element (REE) mineral concentrate produced during Defense Metals’ highly successful 26-tonne flotation pilot-plant that yielded a mineral concentrate averaging 7.4% NdPr oxide (neodymium-praseodymium)[1].
The road accessible Wicheeda REE Property is located close to infrastructure approximately 80 kilometres northeast of Prince George, British Columbia (BC). The Wicheeda project has indicated mineral resources of 4,890,000 tonnes averaging 3.02% LREO (Light Rare Earth Elements) and inferred mineral resources of 12,100,000 tonnes averaging 2.90% LREO[2].
Highlights of the additional infill hydrometallurgical test results conducted at SGS Canada Inc. (“SGS”) Lakefield Site are as follows:
- Increased REE extraction from 91.5% to 97.3% from flotation concentrate (~75% from bulk sample feed) into a chloride-based leach solution compared to initial testing3 (CC-21, Table 1)
- Decreased REE losses via milder gangue leach compared to the base-case flowsheet[3]
- Simplification of flowsheet by removing re-grind step and reducing caustic dosage on re-crack (CC-20) yielded comparable REE extraction of 95.8% from flotation concentrate (~74% from bulk sample feed)
Craig Taylor, CEO of Defense Metals, stated: “Our decision to conduct additional infill hydrometallurgical test-work has yielded significant REE recovery gains approaching 100% REE extraction from the flotation concentrate. Perhaps more importantly, this additional testing has advanced the Wicheeda REE separation flowsheet such that we able to “tune” process variables (chiefly: grind size, acid, and caustic concentrations) to achieve a balance of minimizing REE leach losses and maximizing impurity removal. This level of process control will de-risk our planned hydrometallurgical pilot plant and contribute to greater flexibility in design of a future commercial-scale hydrometallurgical plant.”
About the Wicheeda REE Property
The 1,708 hectare Wicheeda REE Property, located approximately 80 km northeast of the city of Prince George, British Columbia, is readily accessible by all-weather gravel roads and is nearby to infrastructure, including power transmission lines, the CN railway and major highways.
Geologically, the property is situated in the Foreland Belt and within the Rocky Mountain Trench, a major continental geologic feature. The Foreland Belt contains part of a large alkaline igneous province, stretching from the Canadian Cordillera to the southwestern United States, which includes several carbonatite and alkaline intrusive complexes hosting the Aley (niobium), Rock Canyon (REE), and Wicheeda (REE) deposits.
Qualified Person
The scientific and technical information contained in this news release as it relates to the Wicheeda REE Property has been reviewed and approved by Kristopher J. Raffle, P.Geo. (BC) Principal and Consultant of APEX Geoscience Ltd. of Edmonton, AB, a director of Defense Metals and a “Qualified Person” as defined in National Instrument 43-101 – Standards of Disclosure for Mineral Projects. Mr. Raffle verified the data disclosed which includes a review of the analytical and test data underlying the information and opinions contained therein.
Methodology and QA/QC
Hydrometallurgical product assays for neodymium was determined via lithium-borate fusion of a 0.5-gram sample analyzed via wavelength dispersion X-ray fluorescence (WD-XRF). The remaining rare earth elements for the head sample were determined via 0.5-gram sodium-peroxide fusion multi-element ICP-MS.
The SGS analyses included a quality assurance / quality control (QA/QC) program including the insertion of rare earth element standard and blank samples. Defense Metals detected no significant QA/QC issues during review of the data. Defense Metals is not aware of any drilling, sampling, recovery or other factors that could materially affect the accuracy or reliability of the data referred to herein. SGS is an ISO/IEC 17025 and ISO9001:2015 accredited laboratory. SGS is independent of Defense Metals Corp. and the Qualified Person.
