Arrow

Rook 1

IsoEnergy

Southwest Athabasca Basin

NexGen has the most significant land position the southwest Athabasca Basin in Saskatchewan, Canada where it holds 199,576 hectares. This portfolio is considered to be the among the most prospective uranium properties known given the mineralization discovered to date in the southwest along the Patterson Corridor, which hosts the Arrow Deposit, part of the Rook I project.  Furthermore, considering the extent of undrilled target areas near known mineralization, this corridor is likely one of the most endowed mineral belts. Through its subsidiary IsoEnergy Ltd, NexGen also holds a portfolio of highly prospective uranium exploration properties in the eastern side of the Athabasca Basin.

In February 2021, NexGen announced the positive results of an independent Feasibility Study (“FS”), Mineral Reserve, and Mineral Resource update of the basement-hosted Arrow Deposit.  The Company's 100%-owned Rook I project hosts the Arrow Deposit which is principally comprised of Measured Mineral Resources – the highest level of confidence determination within Mineral Resources – with Measured Mineral Resources of 209.6 M lbs of U3O8 contained in 2.18 M tonnes grading 4.35% U3O8, Indicated Mineral Resources of 47.1 M lbs of U3O8 contained in 1.57 M tonnes grading 1.36% U3O8, and Inferred Mineral Resources of 80.7 M lbs of U3O8 contained in 4.40 M tonnes grading 0.83% U3O8 (see the Company's technical disclosure statement: http://www.nexgenenergy.ca/corporate/corporate-governance/). Mineralization at the Arrow Deposit is defined by an area comprised of several steeply dipping shears named A0 through A5, which locally host high grade uranium mineralization. The mineralized area is 315 m wide with an overall strike of 980 m.  Mineralization is noted to occur 100 m below surface and extends to a depth of 980 m.  The individual shear zones vary in thickness from two metres to 60 m. The Arrow Deposit is open in most directions and at depth.  The vertical mineralization of the Arrow deposit lends itself to conventional mining methods, such as long hole open stoping that is currently assumed for the Project.  Additionally, the use of both transverse and longitudinal stoping allows for a high degree of selectivity when mining the high-grade ore body.  The FS defines Probable Mineral Reserves of 239.6 M lbs of U3O8 contained in 4,575 kt grading 2.37% U3O8 from the Measured and Indicated Mineral Resources. 

Arrow is a 100% land-based, basement-hosted, and high-grade uranium discovery which is the largest development-stage uranium deposit in Canada. Additionally, the Company made the "South Arrow" discovery (July 2017), the “Harpoon” discovery (August 2016), the "Bow" discovery (March 2015) and the Cannon discovery (April 2016) 400 m, 4.7 km, 3.7 km and 1.3 km away from Arrow, respectively. Harpoon is the most significant mineralized area discovered since the discovery of Arrow. The company remains well-funded to continue through advanced engineering in support of mine and mill construction at the Arrow Deposit, and for further exploration drilling on the Rook I property.

IsoEnergy Ltd.

The Company holds a 51 % interest in IsoEnergy Ltd. (www.isoenergy.ca) which holds a portfolio off strategically located and prospective assets in the eastern Athabasca Basin including a 100%-interest in the Thorburn Lake project which is located southwest of the Radio property and 7 km east of Cameco's Cigar Lake mine.