West Arnhem-Nabarlek Project

New high-grade uranium (copper-gold) drill targets in a proven mineral system

The Opportunity


The West Arnhem-Nabarlek Project comprises a dominant 5,963km2 tenement package located in the Alligator Rivers Uranium Province (ARUP) of the Northern Territory, a Proterozoic mineral province which is known for its world-class uranium deposits. At the heart of the project lies the historical Nabarlek Uranium Mine, considered Australia's highest-grade uranium mine with a previous production of 24 Mlbs @ 1.84% U3O8.

New assessment of historical data by the Company has revealed potential for other commodities including high-grade copper-gold, previously overlooked by uranium focused explorers. The former single-commodity focus for uranium within the project area has seen the copper-gold and base metal potential lie dormant for decades. DevEx is actively exploring for both copper-gold and uranium in the region.

Figure 1: Location of the West Arnhem Nabarlek Project, Northern Territory.



DevEx has identified near-mine exploration drill targets across two key areas, the Nabarlek and U40 prospects. The Company is currently progressing towards a drill program, following the completion of all regulatory approvals. 

Figure 2: Regional geology of the eastern Alligator River Uranium Province showing pre-mining endowment of uranium and gold deposits, and DevEx Resources Limited’s tenement holdings.

Nabarlek Prospect


DevEx completed a 3D Induced Polarisation (IP) geophysical survey which resulted in the identification of a chargeability anomaly beneath the historical Nabarlek Uranium Mine. The IP survey was undertaken to map nearmine extensions to alteration associated with the uranium mineralisation around the old open pit, and the target identified has potential to host a repetition of the high-grade Nabarlek uranium system.

Please refer to ASX Announcement – ‘Large drill target defined below Nabarlek Uranium Mine, West Arnhem Project, NT’ – 9 October 2018 for full details.

Figure 3: Chargeability anomaly defined beneath the historical Nabarlek Uranium Mine (historical production of 24 million pounds of U3O8) in a recently completed 3D Induced Polarisation (IP) geophysical survey.

U40 Prospect


An IP survey completed has identified a clear chargeable anomaly located down-dip from an isolated pod of high-grade uranium-copper-gold mineralisation at the U40 Prospect. Previous intercepts in diamond core holes that define the high-grade pod include:

  • 6.3m at 7.23% U3O8, 1.9% Cu and 0.66g/t Au from 75.5m (NAD7492)
  • 12.3m at 0.73% U3O8, 2.03% Cu and 1.77g/t Au from 78.9m (NAD7493)

The IP anomaly is interpreted to represent alteration associated with a larger body of mineralisation, with the previous high-grade intercepts interpreted to represent an isolated pod separated from the main body by faulting.

Please refer to ASX Announcement – ‘Uranium-copper-gold drill target defined at West Arnhem Project, NT’ – 12 September 2018 for full details.

Figure 4: Pole-Dipole Chargeability Anomaly at U40 Prospect where previous drilling has encountered an isolated pod of high-grade uranium copper gold mineralisation within a broad sericite-pyrite alteration zone.



More than US$10 billion worth of uranium (in-ground value) has been produced from the ARUP over the past 30 years, resulting in the ground being tightly controlled by major companies with a sole focus on uranium. In addition, historical exploration has been heavily focused on uranium mineralisation, with the potential for multi-metal mineral systems largely overlooked.

DevEx completed a major review of the broader exploration potential of the West Arnhem Project in 2017. This included a re-evaluation of other metal deposits discovered historically (e.g. the 756,000oz Coronation Hill gold and PGE deposit and the 378,000oz Jabiluka II gold deposit) and a reassessment of historical ore grade copper and gold intercepts which were encountered during uranium-focused exploration campaigns.

For example, drilling in 2010 by Cameco Australia Pty Ltd at the U40 prospect encountered significant copper, gold and base metal + PGE mineralisation, including:

  • 12.3m at 2.03% Cu and 1.77g/t Au, including 2.6m at 8.13g/t Au and 2.53g/t PGE (NAD7493)

For the latest project overview, view our Investor Presentation.

Related Documents

Click Here for Mine Management Plan - West Arnhem

Click Here for Mine Management Plan - Nabarlek