Niocorp Developments Ltd (NB)

[Skiluc]

NioCorp Demonstration Plant Achieves Key Phase 1 Milestone



Successful production of high-purity calcium and magnesium carbonates from Elk Creek ore points to potential efficiency gains in NioCorp’s processing flow sheet as well as possible new commercial products for the Project, once sufficient project financing is obtained to allow the Project to proceed

CENTENNIAL, Colo., October 25, 2022 — NioCorp Developments Ltd. (“NioCorp” or the “Company”) (TSX:NB) (OTCQX:NIOBF) today announced that its demonstration-scale processing plant (the “demonstration plant”) in Quebec, Canada has now completed demonstrating its planned process for removing calcium and magnesium from ore obtained from the Elk Creek Critical Minerals Project (the “Project”).

This positive result, which is part of Phase I operations of the demonstration plant, is a key milestone in NioCorp’s proposed optimization of its process flow sheet for the Project, which was designed by L3 Process Innovation (“L3”) and NioCorp.

The well-known and time-tested process NioCorp is employing to remove calcium and magnesium carbonates from the ore using thermal treatment and leaching is part of the demonstration plant’s Phase I flowsheet. This step has operated successfully, and the removed calcium and magnesium were produced at demonstration scale as a mixed calcium and magnesium carbonate. Removing carbonate minerals in this fashion is expected to reduce the size of the follow-on planned production steps and make them more efficient.

Characterization of the calcium and magnesium carbonate from demonstration plant production runs has demonstrated very low levels of impurities, and an overall 99% purity of the mixed calcium-magnesium carbonate.

The Elk Creek resource is a carbonatite and its mineralization is predominantly carbonate minerals. The Elk Creek Project Mineral Resource estimate does not include calcium or magnesium as sufficient exploration and sampling has not been completed to determine whether there are reasonable prospects for eventual economic extraction. In light of these results, however, the Company expect to conduct an assessment of adding these two elements to the Mineral Resource as well as to assess the potential salability of the material that was produced from the demonstration plant, once sufficient project financing is obtained to allow the Project to proceed.

Phase I demonstration plant operations will continue with calcination and a ramp-up of leaching operations as testwork and assembly of Phase II and Phase III of the demonstration plant’s planned operations proceed in parallel.

“The team at L3 has been working very hard to complete Phase I of the demonstration plant and deliver results. We look forward to the completion of the remainder of the demonstration plant operations, and most importantly, the rare earth metallurgical performance metrics showing the full potential economic benefits of rare earths for the Elk Creek Project,” said Scott Honan, NioCorp’s Chief Operating Officer.

QUALIFIED PERSONS:
Eric Larochelle, B.Eng., Co-Owner, L3 Process Development, a Qualified Person as defined by National Instrument 43-101, has reviewed and approved the technical information contained in this news release.
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For More Information:
Jim Sims, Corporate Communications Officer, NioCorp Developments Ltd., 720-639-4650, [e-mail]