NEWS

Vancouver, British Columbia – April 13, 2015 – NioCorp Developments Ltd. (“NioCorp” or the “Company”) [TSX: NBOTCQX: NIOBF; and FSE: BR3] On behalf of our shareholders, NioCorp is pleased to announce the completion of a positive Preliminary Economic Assessment (PEA) study for the Elk Creek Niobium project.

Highlights of the PEA include:

• Pre-tax NPV of US$821 million with an IRR of 15.7%
• After-tax NPV of US$562 million with an IRR of 13.9%
• Average EBITDA of US$177 million annually
• A direct cash production cost for ferroniobium of US$6.50 per kg of niobium at an annualized production rate of 7,500 tonnes of ferroniobium per year for full production years, net of titanium dioxide and scandium trioxide credits
• Annual production of 23,000 tonnes of titanium dioxide and 12.8 tonnes of scandium trioxide
• An upfront capital cost of US$653 million, which includes US$136 million for the development of an underground mine and US$517 million for mineral processing, metallurgical and infrastructure costs
• Total upfront capital costs of US$919 million, which includes contingency and owner’s costs

The basis for the PEA is a 3,700 tonne per day production rate over a 36 year operating life with an average grade of 0.82% Nb2O5.  The NI 43-101 compliant resource supporting this production rate was disclosed in the Company’s press release of February 20, 2015.  The PEA study was completed by SRK Consulting of Lakewood, Colorado and Roche Ltd. of Quebec City, Quebec.

In addition to the underground mine, the Elk Creek PEA includes a surface crushing, grinding and mineral processing operation to produce a niobium concentrate.  The niobium concentrate would be fed to a hydrometallurgical operation that would produce a niobium precipitate as well as titanium dioxide and scandium trioxide co-products.  A final pyrometallurgical step would convert the niobium precipitate to ferroniobium using an aluminothermic reduction process.  In order to support these processing steps, a number of ancillary facilities would be constructed, including stockpile areas, water pumping and treatment facilities, reagent and fuel storage areas, warehousing, utility installations, office space and a tailings impoundment.  The underground mine would be accessed by a shaft and mined using longhole stoping methods with paste backfill utilizing tailings from the mineral processing operation.

“The PEA results are an important milestone in the development of the Elk Creek resource, and I am very pleased to be able to announce results that demonstrate an extremely strong cash flow and very low ferroniobium production costs.” said Mark Smith, Executive Chairman of NioCorp.  “We will use these results as the basis for a bankable feasibility study for the project, and will continue to pursue the most aggressive schedule possible to bring this world-class resource into production.  As with many projects of this size and scope, the return is sensitive to the discount rate. The after tax return ranges from US$940 million to US $420 million with a discount rate between 6 – 9%. We have successfully removed many of the risks associated with the project and look forward to further de-risking as we move the project forward. I am looking forward to the completion of the formal PEA report in the near future.”

The PEA utilizes pricing of US$45/kg for Nb, US$2.10/kg for TiO2 and US$3,500/kg for Sc.  The pricing model anticipates an increase in realized pricing for Nb to US$46/kg in year 4 of the operation, and US$48/kg in year 5.  Pricing for Sc and TiO2 is held constant over the 36 year operating life.

Qualified PersonsMartin Pittuck, MSc., C.Eng, MIMMM of SRK Consulting (UK) Ltd., a Qualified Person as defined by National Instrument 43-101, is responsible for the Elk Creek resource estimation and has read and approved the technical information contained in this news release.

Joanna Poeck, B.Eng., SME-RM, MMSA-QP, a Qualified Person as defined by National Instrument 43-101, is responsible for the Elk Creek mine plan resource and has read and approved the technical information contained in this news release.

Ben Parsons, MSc, MAusIMM (CP) of SRK Consulting (US) Inc., a Qualified Person as defined by National Instrument 43-101, is responsible for the Elk Creek resource estimation and has read and approved the technical information contained in this news release.

Alain Dorval, B.Sc, Roche Consulting Group Limited, a Qualified Person as defined by National Instrument 43-101, is responsible for the Elk Creek mineral processing program and has read and approved the technical information contained in this news release.    Eric Larochelle, B.Eng, Roche Engineering Inc, a Qualified Person as defined by National Instrument 43-101, is responsible for the Elk Creek hydrometallurgical program and has read and approved the technical information contained in this news release.

About the Company:  NioCorp is 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 previously announced a NI43-101 compliant resource with an effective date of February 20, 2015 reporting an Indicated Resource of 80.5 million tonnes grading 0.71% Nb2O5, 2.68% TiO2 and 72 ppm Sc and an Inferred Resource of 99.6 million tonnes grading 0.56% Nb2O5, 2.31% TiO2 and 63 ppm Sc (at a 0.3% Nb2O5 cutoff grade).  Niobium is mainly used in the form of Ferro-Niobium to produce HSLA (High Strength, Low Alloy) steel, which is a lighter, stronger steel used in automotive, structural and pipeline applications.  The U.S. imports 100% of its niobium needs.  Titanium in the form of an oxide is used extensively as a pigment in paints, plastics and papers.  As a metal, titanium is used in aerospace applications, armor, chemical processing applications, marine hardware applications, medical implants, power generation and in sporting goods. Scandium is used in solid oxide fuel cells (SOFCs) and aluminum-scandium alloys, as well as in ceramics, electronics, lasers and lighting applications.

For further information, contact the Company at (604) 568-7365 or via email at [email protected]

ON BEHALF OF THE BOARD

“Peter Dickie”

 Director and President

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