TSX-V-listed Defense Metals has started a confirmatory pilot flotation plant test programme for its wholly-owned Wicheeda rare earths project, located near Prince George, British Columbia, Canada.

The programme will be conducted at the SGS Canada metallurgical facility in Lakefield, Ontario.

Defense Metals has engaged SGS Canada to undertake the programme, which is designed to confirm the results of the 2021 pilot plant, further advance metallurgical development, generate flotation concentrate for hydrometallurgical pilot plant work and support future engineering studies for the Wicheeda project.

The programme will use about 30 t of drill core material from the Wicheeda deposit in two subsamples representing planned production from years one through five and year six onwards of the prefeasibility study (PFS) mine plan.

SGS was selected based on its experience and reputation as the benchmark for quality and integrity in the collaborative design and execution of a pilot plant of this type, Defence Metals says.

The programme will be managed on behalf of Defense Metals by chief metallurgical consultant JR Goode, who has had an extensive career in the design, monitoring and interpretation of beneficiation and hydrometallurgical testwork.

He has over 60 years of experience as a metallurgist working on numerous rare earth projects located in Canada, the US, China, Australia, Brazil, Greenland, Russia and elsewhere.

The primary objective of the pilot flotation campaign is to generate a representative rare earth flotation concentrate grading about 50% total rare earth oxides.

The concentrate produced during the pilot programme will be used in a planned downstream hydrometallurgical pilot plant aimed at confirming and optimising the general process conditions of the PFS with the representative concentrate generated from this pilot flotation programme.

In addition to concentrate production, the continuous pilot-scale operation will generate representative process tailings for downstream testing and characterisation.

The pilot plant will also confirm metallurgical performance under continuous operating conditions while providing valuable engineering and process design data for future project development activities, the company points out.

To further support engineering design, Defense Metals has engaged Jenike & Johanson to conduct bulk solids handling testwork on various production plant process streams using samples generated during the pilot plant operation.

The testing is expected to provide important design criteria related to materials handling for process plant design.

SGS has completed pre-pilot characterisation work, including head assays, grindability testing, laboratory-scale flotation testing and pilot plant setup activities.

Pilot plant operations are scheduled to start on May 12 and are expected to continue for about five weeks.

“We are very pleased to commence this important pilot flotation campaign with SGS Lakefield, which marks another major step in advancing the Wicheeda project toward development.

“The generation of a representative high-grade rare earth concentrate for downstream hydrometallurgical testing is a critical component in further derisking the project and refining our process flowsheet. The pilot programme will also provide valuable engineering and operational data needed to continue progressing Wicheeda as a potential North American source of rare earth materials,” says Defense Metals CEO Mark Tory.