NioCorp Drilling Update

VANCOUVER, BRITISH COLUMBIA--(Marketwired - Jun 3, 2014) - NioCorp Developments Ltd. ("NioCorp" or the "Company") (TSX VENTURE:NB)(OTCQX:NIOBF)(FRANKFURT:BR3) is pleased to provide the following update.

On June 2nd, a second drill rig completed mobilization to the project site, and is expected to commence drilling operations on June 3rd. The first drill rig has been on site for two weeks, and as of June 1st has completed approximately 560 meters of core drilling. The core will be assayed for resource enhancement, and will also be utilized for geotechnical, geochemical, and metallurgical studies. The boreholes will be further utilized for geotechnical and hydrologic test work once core extraction is complete. Drilling with both rigs will continue on a 24 hour schedule until completion of phase one, with phase two drilling commencing immediately thereafter.

The drill program was designed after an extensive review process involving the Company's key advisors, SRK Consulting ("SRK") of Lakewood, Colorado, and Dahrouge Geological Consulting Ltd. ("Dahrouge") of Edmonton, Alberta. The first of three phases of this program will consist of approximately 4,200 meters of core drilling, with all three phases totaling 12,000 meters, if necessary, to fulfill desired corporate outcomes.

Preparation work was completed at the outset of the drill program and Niocorp's exploration facilities are now fully operational, with staffing from NioCorp, SRK, Dahrouge and additional locally sourced staff. Additional technical personnel from the University of Nebraska in Lincoln are also expected to join the project team shortly. The elevated staffing levels will allow for steady processing of drill core, enabling a rapid turnaround on testing results. On site facilities include two steel-frame, concrete floored core storage and processing buildings built by Molycorp in the 1980s, that are capable of handling the expected drill core production rates. A small office in the nearby town of Tecumseh provides additional space for engineering and technical planning work. In order to better oversee the off-site work on the project, the Company is establishing an office in Denver, Colorado. Both SRK and Hazen Research Inc. ("Hazen"), who are integrally involved in the ongoing metallurgical studies, are located in the Denver area.

"I am pleased with the pace of the initial drilling activities on the project," said Mark Smith, NioCorp's CEO. "We have a very capable and experienced team working on the project, and I look forward to seeing results from our efforts in the near future."

About the Company: NioCorp are developing the only primary niobium deposit known to be under development in the U.S., and the highest grade undeveloped niobium deposit in North America, located near Elk Creek, Nebraska. The Company has published an NI 43-101 resource of 19.3 Million tonnes grading 0.67% Indicated, containing over 129,182 tonnes of Nb₂O₅, and 83.3 Mt grading 0.63% Inferred, containing over 523,844 tonnes of Nb₂O₅). Niobium is mainly used in the form of Ferro-Niobium to produce HSLA (High Strength, Low Alloy) steel, to produce lighter, stronger steel for use in automotive, structural and pipeline industries. The U.S. imports 100% of its niobium needs.

ON BEHALF OF THE BOARD

Peter Dickie, Director, President and Corporate Secretary

Neither TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.

Certain statements contained in this press release may constitute forward-looking statements. Such forward-looking statements are based upon NioCorp's reasonable expectations and business plan at the date hereof, which are subject to change depending on economic, political and competitive circumstances and contingencies. Readers are cautioned that such forward-looking statements involve known and unknown risks, uncertainties and other factors that may cause a change in such assumptions and the actual outcomes and estimates to be materially different from those estimated or anticipated future results, achievements or position expressed or implied by those forward-looking statements. Risks, uncertainties and other factors that could cause NioCorp's plans or prospects to change include changes in demand for and price of commodities (such as fuel and electricity) and currencies; changes or disruptions in the securities markets; legislative, political or economic developments; the need to obtain permits and comply with laws and regulations and other regulatory requirements; 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 labour 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 or development activities; the speculative nature of mineral exploration and development, including the risks of diminishing quantities of grades of reserves and resources; and the risks involved in the exploration, development and mining business. NioCorp disclaims any intention or obligation to update or revise any forward-looking statements whether as a result of new information, future events or otherwise.