NexGen Drills 3 Mineralized Holes at Rook I from 11 Highly Altered Holes Along Strike from PLS

VANCOUVER, BRITISH COLUMBIA--(Marketwired - Oct 16, 2013) - NexGen Energy Ltd. (TSX VENTURE:NXE) ("NexGen" or the "Company") is pleased to announce that it has completed its first phase drill program totalling 3,032m on Rook 1. Rook 1 is immediately adjacent to, and up strike approximately 2.1km northeast of the high-grade uranium discovery at Patterson Lake South (PLS) made by Fission Uranium/Alpha Minerals (see Figure 1).

Highlights

• 12 completed widely spaced holes tested a 1.6 km x 1.2 km area in which 11 holes contained significant clay and hematite alteration (see Figure 1).

• Three holes on three separate parallel conductors intercepted mineralization.

• Hole RK-13-05 (which is located on the conductor interpreted to be an extension of the PLS3b conductor which hosts the high grade PLS discoveries) encountered elevated levels of radioactivity (max total gamma 4,379 cps) over 2.7m within a 29m wide shear zone containing breccias, faults, fractures, and a variety of veining. Alteration features include massive silicification, clay alteration, hematite, chlorite, and desilicification (see Figure 2). Visible pitchblende was identified at a down-hole depth of 220.5-220.8m, within heavily altered and hematised breccia (see Figure 3).

• Mineralization in holes RK-13-03 and -06 is located on other parallel conductors interpreted to be possible repetitions of the main PLS 3b conductor.

Two rigs completed 12 holes in an area of approximately 1.6km x 1.2km, with the closest two holes being 200m apart. Fertile receptive basement graphitic lithologies were intersected in 11 of the 12 completed holes below 48.7-82.6m of glacial and Cretaceous overburden. The 11 holes also contained significant clay and hematite alteration. All 12 holes contained evidence of repeated structural dislocation, being primarily brecciation, offset faulting, shearing, and veining.

Table 1 Rook 1 mineralization intercepts

Measurement by Mt Sopris 2PGA-1000 gamma probe

Leigh Curyer, CEO of NexGen States, "We are very pleased with the early results of this first drilling program at Rook1. This initial drilling program at Rook 1 has identified several large alteration and mineralisation systems. The program was specifically designed to confirm the geological interpretation of several geophysical surveys over a large area, to discover new mineralisation, and to provide a firm basis for tightly-targeted follow up drilling programs. It has achieved all three aims above expectation. We are planning a significantly large winter program to follow up in the immediate vicinity of these mineralized holes and test additional target zones identified by geophysical surveys we have yet to drill."

All photographs of core and drill location maps will be available at under photos at http://www.nexgenenergy.ca/projects/rook-i/

Figure 1. Rook 1 drillhole locations, summer 2013: http://file.marketwire.com/release/904628.pdf

Figure 2. RK-13-05: 192-231m downhole showing 29m mineralized shear zone: http://file.marketwire.com/release/904628.pdf

Figure 3. RK-13-05, 220.8m: pitchblende veinlet in haematised breccia: http://file.marketwire.com/release/904628.pdf

Figure 4. RK-13-05, 215m: sheared altered mineralized breccia: http://file.marketwire.com/release/904628.pdf

Note that radiometric readings reported in this news release are measured in total counts per second (cps) using a Mt Sopris 2PGA natural gamma radiation down hole probe. Total count radiation readings may not be directly related to actual uranium as other radioactive elements, such as thorium and potassium, are also present in the rock interval measured. The downhole gamma probe data is used purely as an indication of the presence of radioactive materials. General background readings for the project are in the range of 10-200 cps. The actual radioactive source element and grade of the radioactive material will be determined by means of chemical analytical techniques provided by the Saskatchewan Research Council, Saskatoon, Saskatchewan. True thicknesses for the reported radioactive intersections have yet to be determined.

NexGen defines an intercept of >0.5m @ 300 cps as indicative of uranium mineralisation, to be confirmed by chemical analysis. Samples have been sent to SRC laboratory in Saskatoon for this analysis, and results are expected within 6-8 weeks.

Basement lithologies intersected comprise a variety of quartz-feldspar-biotite (± garnet) microgneiss and gneiss, with local graphitic units. Examination of all basement lithologies intersected indicate that the entire area drilled comprises a strongly tectonised zone with a number of discrete shear zones associated with hematitic and clay alteration, within a variety of graphitic material. As previously noted, graphitic lithologies have been observed in the basement at Rook 1 mainly as discrete lithological units. Other thin graphitic occurrences have been logged as graphitic material associated with structures such as shears or slip planes.

For full detail of each drill hole alteration intervals, type and intensity, together with graphitic lithologies, please visit http://www.nexgenenergy.ca/projects/rook-i/

Qualified Person

Andrew Browne, FAusIMM(CP), NexGen's Vice President, Exploration & Development, is a "qualified person" for the purposes of National Instrument 43-101 - Standards of Disclosure for Mineral Projects, and has reviewed and approved the contents of this news release.

About NexGen

NexGen is a British Columbia corporation with a focus on the acquisition, exploration and development of Canadian uranium projects. NexGen has a highly experienced team of exploration professionals with a track record in the discovery of unconformity-style uranium deposits in Canada.

The TSXV has neither approved nor disapproved the contents of this press release. Neither the TSXV nor its Regulation Services Provider (as that term is defined in the policies of the TSXV) accepts responsibility for the adequacy or accuracy of this release.

Forward-Looking Information

This news release contains "forward-looking information" within the meaning of applicable Canadian securities laws. Generally, but not always, forward looking information is identifiable by the use of words such as "will" and planned" and similar expressions. Forward-looking information is based on the then current expectations, beliefs, assumptions, estimates and forecasts about the Company's business and the industry and markets in which it operates. Such information is not a guarantee of future performance and undue reliance should not be placed on forward-looking information. Assumptions and factors underlying the Company's expectations regarding forward-looking information contained herein include, among others: that general business and economic conditions will not change in a material adverse manner; that financing will be available if and when needed on reasonable terms; that the Company's current exploration activities can be achieved and that its other corporate activities will proceed as expected; that third party contractors, equipment and supplies and governmental and other approvals required to conduct the Company's planned exploration activities will be available on reasonable terms and in a timely manner. Further, mineralization on properties held by third parties adjacent to NexGen's properties (including Patterson Lake South) are not necessarily indicative of mineralization on NexGen's properties.

Although the assumptions made by the Company in providing forward looking information are considered reasonable by management at the time the forward-looking information is given, there can be no assurance that such assumptions will prove to be accurate. Forward-looking information also involves known and unknown risks and uncertainties and other factors, which may cause actual events or results in future periods to differ materially from any projections of future events or results expressed or implied by such forward-looking information, including, among others: risks related to the availability of financing on commercially reasonable terms and the expected use of the proceeds; changes in the market; potential downturns in economic conditions; industry conditions; actual results of exploration activities being different than anticipated; changes in exploration programs based upon results of exploration; future prices of metal; availability of third party contractors; availability of equipment and supplies; failure of equipment to operate as anticipated; accidents, effects of weather and other natural phenomena and other risks associated with the mineral exploration industry; environmental risks; changes in laws and regulations; community relations; and delays in obtaining governmental or other approvals or financing. There can be no assurance that forward-looking information will prove to be accurate, as actual results and future events could differ materially from those anticipated, estimated or intended. NexGen undertakes no obligation to update or reissue forward-looking information as a result of new information or events except as required by applicable securities laws. The reader is cautioned not to place undue reliance on forward-looking information.