NioCorp Developments Ltd. (NASDAQ:NB), a leading U.S. critical minerals developer, is pleased to report assay results from the first completed diamond drill hole from its drilling program at its critical minerals project in Southeast Nebraska.

The drilling program and associated technical work is being funded by the Pentagon and is designed to support the conversion of a portion of the Elk Creek Project’s Indicated Mineral Resources into Measured Mineral Resources and the subsequent conversion of a portion of its Probable Mineral Reserves into Proven Mineral Reserves. The drilling program was designed to help meet Mineral Resource and Mineral Reserve classification requirements associated with the ongoing review of the Company’s application for up to $800 million in potential debt financing by the Export-Import Bank of the United States.

Assays of the other completed drill holes during the now complete drilling program are underway at external laboratories.

“We appreciate the Pentagon’s continued partnership in advancing this important work,” said Mark A. Smith, CEO and Chairman of NioCorp. “These results are consistent with the existing Mineral Resource model for the Elk Creek deposit along with the lithologies logged by the field geology team when the hole was drilled, and confirm that the deposit is well understood. We look forward to receiving the remaining assay results, completing updates to our Mineral Resources and Mineral Reserves and continuing our discussions with EXIM Bank as we work to advance financing efforts for the Elk Creek Project.”

Table 1: Summary of Significant Drill Hole Results

Figure 1: Drill Hole Location Map – Elk Creek Project, Southeast Nebraska

Figure 2: NEC25-024 – Drill Hole Location Map

Figure 3: NEC25-024 – Cross Section

The drilling program was divided into two phases. Phase I of the program comprised 11 HQ diamond drill holes totaling approximately 7338.5 meters, of which 731.67 meters were drilled in connection with the first drill hole (NEC25-024), with Phase II including four HQ holes totaling approximately 2,235 meters. Two additional geomechanical drill holes totaling approximately 1,950 meters were also completed as part of an accelerated effort to to support underground mine design related to access ramp development.

Table 2: Summary of Drill Hole Coordinates

Sampling, Analytical Methods and QA/QC Protocols

All drilling was completed using a Boart Longyear LF160 diamond drill rig with HQ size core. Drill core samples from Phase I of the program were shipped to SGS Analytical’s preparation facility in Denver, Colorado for standard sample preparation which includes weighing, drying, crush (< 4 kg) up to 75% passing 2 mm, riffle split (250 g) and pulverize (Cr steel) to 90% passing 75 µm. The samples were subsequently analyzed using GE-ICM91A50 (sodium peroxide fusion with subsequent analysis by ICP and ICP/MS), GO_XRF72+GC_XRF76V (Nb₂O₅ and Ta2O5). The drill core was saw-cut into half-core with one half being sent for geochemical analysis and the other half-core remaining in the core box onsite. A quality assurance/quality control protocol was incorporated into the drilling program and included the insertion of certified reference material, silica blanks, duplicate quarters, pulps and rejects all at a rate of approximately 5% respectively.

The assay results discussed in this press release are not measures of reserves or resources as defined in Subpart 1300 of Regulation S-K promulgated by the SEC or National Instrument 43-10. The conversion of assay results in this news release into reserve or resource estimates in compliance with S-K 1300 and NI 43-101 requires additional technical work and analysis that remains ongoing. In addition, the assay results discussed in this press release may not be indicative of future assay results, and may not be indicative of our ability to convert any of the Elk Creek Project’s Indicated Mineral Resources into Measured Mineral Resources or the subsequent conversion of any of its Probable Mineral Reserves into Proven Mineral Reserves. As such, the conversion of reported mineral resources to mineral reserves should not be assumed, and the reclassification of reported mineral resources from lower to higher levels of geological confidence should not be assumed.

Qualified Persons:

Trevor Mills, P.G., SME-RM, Principal Geologist / US Operations Manager of Dahrouge Geological Consulting USA Ltd., a Qualified Person as defined by NI 43-101, has reviewed and approved the technical information and verified the data contained within the news release. Mr. Mills has verified all scientific and technical data disclosed in this news release including the sampling and QA/QC results, and certified analytical data underlying the technical information disclosed herein. Mr. Mills noted no errors or omissions during the data verification process. The Company and Mr. Mills do not recognize any factors of sampling or recovery that could materially affect the accuracy or reliability of the assay data disclosed in this news release.