NexGen's 72% owned subsidiary, IsoEnergy ( holds a highly prospective portfolio of uranium exploration projects in the historic Eastern Athabasca Basin. This includes a 100%-interest in the Thorburn Lake property located just 7 km east of and on trend with Cameco's Cigar Lake mine which contains proven reserves of 233,600 tonnes at 22.31% U3O8 and probable reserves of 303,500 tonnes at 15.22% U3O8, which yields 216.7 million pounds of U3O8 in the Proven and Probable mineral reserves category ( IsoEnergy raised gross proceeds of over $8 million and trades on the TSX Venture Exchange under the symbol "ISO".

Thorburn Lake Property

The 2008 drill program identified uranium enrichment at the Athabasca Group-basement unconformity, with uranium analyses as high as 90 ppm over 5.1 m. Of the ten holes drilled in 2011, four had significant uranium anomalies associated with alteration envelopes at the unconformity. Drill hole TBN-11-05a was found to have visible pitchblende veins and disseminations. This drill hole yielded a best result of 0.17% U3O8 over 0.6 m within a larger weakly mineralized zone with a grade of 0.019% U3O8 over 8.0 m straddling the unconformity.
The Thorbun project has been undrilled since 2011 and will be followed-up by IsoEnergy in a near-term drill campaign.

(Mineralized intercepts are indicated by red collar markers)
  • Drill hole TBN-08-04 - 487 ppm U from 284.5 - 285.1 m
  • Drill hole TBN-11-05A - 1,430 ppm U from 288.8 - 289.3 m and 910 ppm U from 289.3 - 292.0 m, including 3,610 ppm from 289.3 - 289.9 m
  • Drill hole TBN-11-06 - 432 ppm U from 283.0 - 283.9 m and 204 ppm U from 283.9 - 285.0 m
  • Drill hole TBN-11-13 - 347 ppm U from 290.4 - 291.4 m
  • Drill hole TBN-11-14 - 232 ppm U from 380.5 - 381.0 m
Similarities and Proximity to Cigar Lake


IsoEnergy holds an option to earn an initial 70%-interest in the Radio project which is located in the eastside of the Athabasca Basin and is directly adjacent to Rio Tinto's Roughrider deposit (Rio Tinto acquired Hathor Exploration in 2012 for $654 million). IsoEnergy can earn the 70%-interest by spending an aggregate of $10 million in exploration expenditures by May 31, 2017.
During the summer 2013, NexGen drilled a total of nine holes (totalling 3,472.9 m) at the Radio project and identified clay alteration, structural disruption in the Athabasca sandstone and alteration and structures in the basement rocks. These features are known to occur at or in the vicinity of high-grade uranium mineralization in the Athabasca Basin.

The target areas and drill site locations were defined using a combination of the detailed 2011 airborne magnetic and VTEM electromagnetic surveys, and the 2013 ground resistivity and gravity work. The target areas have resistivity and gravity lows coincident with basement structures interpreted from magnetic surveys and weakly conductive basement lithologies defined by the VTEM survey.
Despite being located 2 km from the Roughrider deposit, the Radio project had never been drill tested prior to NexGen's 2013 drill program and IsoEnergy will be commencing drilling here in the near-term.