Star Metro - NioCorp to Begin Construction of Mine Portal at Its Elk Creek Critical Minerals Project

CENTENNIAL, CO / ACCESS Newswire / December 22, 2025 / NioCorp Developments Ltd. ("NioCorp" or the "Company") (Nasdaq:NB), a leading U.S. critical minerals developer, today announced that its Board of Directors (the "Board") has approved the Company's Mine Portal Project (the "Portal Project"), a major initiative to advance the Elk Creek Critical Minerals Project (the "Elk Creek Project").

The Portal Project will establish the main entrances to the Elk Creek Project underground mine and will serve as the primary access point for personnel, equipment, and materials for the Company's planned underground mining operations. The Board-approved scope also includes excavating to bedrock, drilling and blasting to establish the twin mine ramps, on-site access road construction, as well as on-site supporting infrastructure. Work is expected to begin in Q1 of calendar year 2026 and the current estimated capital cost for the project is approximately $44.6 million.

The portal will provide access for the Company's planned implementation of the Railveyor^™ system, which NioCorp announced in 2024 as the preferred bulk material handling solution for the Elk Creek Project. (See this announcement). Utilizing the Railveyor^™ system replaces the previously planned twin-shaft design and, according to the scoping study, is expected to reduce initial capital costs through simplified underground infrastructure and a shorter pre-development schedule.

The Railveyor^™ system will run on electricity, as will all of NioCorp's underground mining equipment, offering potential environmental, safety, and operational benefits when compared to conventional diesel-powered underground mining systems.

"Approval of the Portal Project is a significant milestone for NioCorp," said Mark A. Smith, CEO and Chairman of NioCorp. "This initiative allows us to advance one of the critical path schedule items for the project as we continue working toward securing the remaining financing needed for the Elk Creek Project. We greatly appreciate the strong support shown by Nebraskans and our project partners as we continue advancing."

"Given the size of this excavation work, the Portal Project really marks the beginning of a major pre-construction activity at the Elk Creek Project site and is an important step toward preparing for underground development," said Scott Honan, President and Chief Operating Officer of NioCorp. "Advancing this work now helps keep our schedule moving. It's going to be exciting for the community to see major activity at the site - something many of us have been looking forward to for quite some time."

Qualified Persons:

Scott Honan, M.Sc., SME-RM, COO of NioCorp Developments Ltd., 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, Chief Communications Officer, NioCorp Developments Ltd., (720) 334-7066, [email protected]

Alex Guthrie, Director, Investor Relations, NioCorp Developments Ltd., (720) 334-7066, [email protected]

@NioCorp $NB #Niobium #Scandium #rareearth #neodymium #dysprosium #terbium #ElkCreek

ABOUT NIOCORP

NioCorp is developing the Elk Creek Project that is expected to produce niobium, scandium, and titanium. The Company also is evaluating the potential to produce several rare earths from the Elk Creek Project. Niobium is used to produce specialty alloys as well as High Strength, Low Alloy steel, which is a lighter, stronger steel used in automotive, structural, and pipeline applications. Scandium is a specialty metal that can be combined with Aluminum to make alloys with increased strength and improved corrosion resistance. Scandium is also a critical component of advanced solid oxide fuel cells. Titanium is used in various lightweight alloys and is a key component of pigments used in paper, paint and plastics and is also used for aerospace applications, armor, and medical implants. Magnetic rare earths, such as neodymium, praseodymium, terbium, and dysprosium are critical to the making of neodymium-iron-boron magnets, which are used across a wide variety of defense and civilian applications.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the United States Private Securities Litigation Reform Act of 1995 and forward-looking information within the meaning of applicable Canadian securities laws. Forward-looking statements may include, but are not limited to, statements regarding the expected scope, timing, sequencing, progression and capital cost of the Portal Project and related pre-construction work at the Elk Creek Project, including the anticipated start dates for access road construction, stormwater infrastructure, portal excavation, marine sediment drill-and-blast activities, ramp foundation work, and arch installation, as well as expectations regarding future underground development and advancement toward construction; NioCorp's expectation of producing niobium, scandium, and titanium, and the potential of producing rare earths, at the Elk Creek Project; and NioCorp's ability to secure sufficient project financing to complete construction of the Elk Creek Project and move it to commercial operation. Forward-looking statements are typically identified by words such as "plan," "believe," "expect," "anticipate," "intend," "outlook," "estimate," "forecast," "project," "continue," "could," "may," "might," "possible," "potential," "predict," "should," "would" and other similar words and expressions, but the absence of these words does not mean that a statement is not forward-looking.

The forward-looking statements are based on the current expectations of the management of NioCorp and are inherently subject to uncertainties and changes in circumstances and their potential effects and speak only as of the date of such statement. There can be no assurance that future developments will be those that have been anticipated. Forward-looking statements reflect material expectations and assumptions, including, without limitation, expectations and assumptions relating to: NioCorp's ability to receive sufficient project financing for the construction of the Elk Creek Project on acceptable terms, or at all; the future price of and demand for metals, including aluminum-scandium alloy; and the stability of the financial and capital markets. Such expectations and assumptions are inherently subject to uncertainties and contingencies regarding future events and, as such, are subject to change. Forward-looking statements involve a number of risks, uncertainties or other factors that may cause actual results or performance to be materially different from those expressed or implied by these forward-looking statements. These risks and uncertainties include, but are not limited to, those discussed and identified in public filings made by NioCorp with the Securities and Exchange Commission and with the applicable Canadian securities regulatory authorities and the following: NioCorp's requirement of significant additional capital; NioCorp's ability to receive sufficient project financing for the construction of the Elk Creek Project on acceptable terms, or at all; NioCorp's ability to achieve the required milestones and receive the full $10.0 million in reimbursement under the Project Sub-Agreement with Advanced Technology International, an entity acting on behalf of the Defense Industrial Base Consortium under the authority of the U.S. Department of War; NioCorp's ability to receive a final commitment of financing from the Export-Import Bank of the United States or other debt financing or financial support on acceptable timelines, on acceptable terms, or at all; NioCorp's ability to access the full amount of the expected net proceeds under the standby equity purchase agreement (the "Yorkville Equity Facility Financing Agreement") with YA II PN, Ltd., an investment fund managed by Yorkville Advisors Global, LP; NioCorp's ability to continue to meet the listing standards of The Nasdaq Stock Market LLC; risks relating to NioCorp's common shares, including price volatility, lack of dividend payments and dilution or the perception of the likelihood of any of the foregoing; the extent to which NioCorp's level of indebtedness and/or the terms contained in agreements governing NioCorp's indebtedness, if any, the Yorkville Equity Facility Financing Agreement or other agreements may impair NioCorp's ability to obtain additional financing, on acceptable terms, or at all; covenants contained in agreements with NioCorp's secured creditors that may affect its assets; NioCorp's limited operating history; NioCorp's history of losses; the material weaknesses in NioCorp's internal control over financial reporting, NioCorp's efforts to remediate such material weaknesses and the timing of remediation; the possibility that NioCorp may qualify as a passive foreign investment company under the U.S. Internal Revenue Code of 1986, as amended (the "Code"); the potential that the business combination with GX Acquisition Corp. II and other related transactions could result in NioCorp becoming subject to materially adverse U.S. federal income tax consequences as a result of the application of Section 7874 and related sections of the Code; cost increases for NioCorp's exploration and, if warranted, development projects; a disruption in, or failure of, NioCorp's information technology systems, including those related to cybersecurity; equipment and supply shortages; variations in the market demand for, and prices of, niobium, scandium, titanium and rare earth products; current and future offtake agreements, joint ventures, and partnerships, including NioCorp's ability to negotiate extensions to existing agreements or to enter into new agreements, on favorable terms or at all; NioCorp's ability to attract qualified management; estimates of mineral resources and reserves; mineral exploration and production activities; feasibility study results; the results of metallurgical testing; the results of technological research; changes in demand for and price of commodities (such as fuel and electricity) and currencies; competition in the mining industry; changes or disruptions in the securities markets; legislative, political or economic developments, including changes in federal and/or state laws that may significantly affect the mining and scandium alloy industries; trade policies and tensions, including tariffs; inflationary pressures; the impacts of climate change, as well as actions taken or required by governments related to strengthening resilience in the face of potential impacts from climate change; the need to obtain permits and comply with laws and regulations and other regulatory requirements; the timing and reliability of sampling and assay data; the possibility that actual results of work may differ from projections/expectations or may not realize the perceived potential of NioCorp's projects; risks of accidents, equipment breakdowns, and labor disputes or other unanticipated difficulties or interruptions; the possibility of cost overruns or unanticipated expenses in development programs; operating or technical difficulties in connection with exploration, mining, development or scandium-alloy production activities; management of the water balance at the Elk Creek Project site; land reclamation requirements related to the Elk Creek Project; the speculative nature of mineral exploration and development, including the risks of diminishing quantities of grades of reserves and resources; claims on the title to NioCorp's properties; the infringement or loss of NioCorp's intellectual property rights; potential future litigation; and NioCorp's lack of insurance covering all of NioCorp's operations.

Should one or more of these risks or uncertainties materialize or should any of the assumptions made by the management of NioCorp prove incorrect, actual results may vary in material respects from those projected in these forward-looking statements.

All subsequent written and oral forward-looking statements concerning the matters addressed herein and attributable to NioCorp or any person acting on its behalf are expressly qualified in their entirety by the cautionary statements contained or referred to herein. Except to the extent required by applicable law or regulation, NioCorp undertakes no obligation to update these forward-looking statements to reflect events or circumstances after the date hereof to reflect the occurrence of unanticipated events.

SOURCE: NioCorp Developments Ltd.

View the original press release on ACCESS Newswire

M.Anderson--SMC