Nex Metals has advanced its Kookynie Tailings Project metallurgical testing, lifting gold recovery significantly and uncovering a promising tungsten by-product opportunity.
- Gold recovery improved from 52% to 71% with carbon-in-leach and light grinding
- Bulk samples confirm consistent ~0.95 g/t gold grades matching historical data
- Tungsten mineral scheelite identified in gravity concentrate as potential by-product
- No harmful environmental elements detected above WHO guidelines
- Next phase focuses on validating processing flowsheet and optimising recoveries
Significant Gold Recovery Gains at Kookynie Tailings
Nex Metals Explorations Ltd (ASX:NME) has made a notable leap in its Kookynie Tailings Project by boosting gold recovery rates from a modest 52% to a more robust 71%. This jump was achieved by integrating carbon-in-leach (CIL) processing and a light grind circuit into their metallurgical test work, marking a 37% relative improvement over previous direct cyanidation methods. The test work, conducted on representative bulk samples, confirms a straightforward and potentially low-cost processing route that could underpin the project's commercial viability.
Representative Sampling Validates Project Scale
Two 50-kilogram bulk samples dug from Tailings Dumps 4 at the Cosmopolitan Gold Mine site returned gold head grades of 0.94 g/t and 0.96 g/t, closely aligning with historical drilling data. This consistency provides confidence that the metallurgical findings reflect the broader tailings inventory rather than isolated pockets of mineralisation. Such validation is critical as it underpins the reliability of recovery rates and the scalability of the processing approach.
Tungsten By-Product Emerges as Value Add
Beyond gold, the metallurgical programme uncovered a tungsten head grade of 0.063% WO₃ within the tailings. The tungsten mineral scheelite was confirmed to concentrate in the gravity circuit, evidenced by its characteristic fluorescence under ultraviolet light. While gold remains the primary focus, this discovery opens the door to a potential secondary revenue stream if tungsten recovery proves commercially viable after further metallurgical and economic evaluation. This dual commodity potential could enhance project economics and investor appeal.
Environmental Profile Supports Processing Plans
Environmental assessments found no deleterious elements exceeding World Health Organization guideline levels, a positive signal for downstream processing and environmental management. This clean profile reduces potential regulatory hurdles and supports the company’s capital-light growth strategy, which includes a joint venture with the Wangkatja Tjungula Aboriginal Corporation (WTAC) and exploration ventures in Western Australia and Egypt.
Next Steps Focus on Process Validation and Optimisation
With a clearer processing flowsheet emerging, Nex Metals plans to validate the proposed circuit and explore finer grind sizes to push gold recoveries even higher. The company’s managing director, Ken Allen, emphasised the importance of this milestone in moving towards an efficient and commercially attractive development pathway. Meanwhile, the tungsten opportunity will be further investigated to assess its integration into the overall processing strategy.
Bottom Line?
Nex Metals’ metallurgical advances at Kookynie position the project closer to commercial reality, but the economic viability of tungsten recovery and final process optimisation remain key hurdles.
Questions in the middle?
- Can tungsten recovery be scaled commercially alongside gold without complicating processing costs?
- What impact will finer grinding and further process validation have on final gold recovery rates and project economics?
- How will environmental permitting and community partnerships influence the timeline to production?