{"id":142946,"title":"Rockfire Resources boosts Molaoi zinc grade by 132.5% in preliminary ore sorting tests","publisher":"Share Talk","author":"sharetalk","published":"2026-11-13T07:16:25+00:00","modified":"2026-11-13T07:16:25+00:00","canonical_url":"https://www.share-talk.com/rockfire-resources-boosts-molaoi-zinc-grade-by-132-5-in-preliminary-ore-sorting-tests/","markdown_url":"https://www.share-talk.com/rockfire-resources-boosts-molaoi-zinc-grade-by-132-5-in-preliminary-ore-sorting-tests.md","json_url":"https://www.share-talk.com/rockfire-resources-boosts-molaoi-zinc-grade-by-132-5-in-preliminary-ore-sorting-tests.json","category":"Mining","categories":["Mining"],"tags":["Australia","David Price","Emirates Gold DMCC","Gold","gold system","Greece","JORC","Lighthouse","maiden","mineral","Molaoi","North Queensland","resource","Rock","Rockfire Resources"],"featured_image":"https://i0.wp.com/www.share-talk.com/wp-content/uploads/2026/11/7bf59304-da43-4978-b0cf-094d3e31334f.png?fit=1727%2C911&quality=80&ssl=1","format":"news","language":"en-GB","content":"[Rockfire Resources plc (LON: ROCK)](https://www.investegate.co.uk/announcement/rns/rockfire-resources--rock/molaoi-update/9873538) has reported encouraging preliminary ore sorting results at its wholly owned Molaoi zinc deposit in Greece, with testing by TOMRA Mining increasing the zinc grade from 5.85% to 13.6%, representing a 132.5% uplift.including X-Ray Transmission (XRT) ore sorting technology in the project’s processing flowsheet, aiming to separate\n\nThe results support the potential inclusion of **X-Ray Transmission (XRT) ore sorting technology** in the project’s processing flowsheet, with the aim of separating zinc-rich material from lower-grade rock before conventional mineral processing.\n\n**The initial feed grade of 5.85% zinc was upgraded to 13.6% in the first sorting stage**, with the high-density product accounting for **34.5% of the original feed mass**.\n\nA second sorting stage produced material grading **11.7% zinc**, representing a **99.5% improvement** over the original feed grade, with cumulative mass recovery reaching 46.8%.\n\nThe third stage recovered additional material grading **9.9% zinc**, equivalent to a **69.7% grade uplift**, bringing the cumulative mass pull to **57.7%**.\n\nImportantly, **the combined sorting process recovered 97.7% of the zinc contained in the original test feed**, indicating that the technology could potentially reject a substantial proportion of lower-grade material while retaining most of the zinc.\n\nThese figures describe successive stages of the same sorting process rather than three separate overall recovery results.\n\n**The test programme was undertaken by TOMRA Mining using 48 quarter-core samples with a combined weight of approximately 65 kilograms**, representing high-grade, medium-grade and waste material from Molaoi.\n\nThe samples were crushed to below 25 millimetres and screened at eight millimetres, with the **8–25mm fraction selected for XRT sorting**.\n\nThe technology uses differences in X-ray absorption to identify particles containing dense minerals, allowing zinc-bearing sulphides to be separated from lower-density waste rock.\n\nRockfire used a cascading approach, progressively adjusting the sorting equipment’s sensitivity to recover material with different density characteristics.\n\n**The results indicate that ore sorting could potentially improve the grade of material entering the processing plant**, reducing the amount of waste requiring downstream crushing, grinding and mineral separation.\n\nAn effective sorting stage could also help offset dilution introduced during underground mining, although this benefit has not yet been demonstrated under commercial operating conditions.\n\n**Chief Executive David Price** described the results as a promising first assessment of the technology’s suitability for Molaoi.\n\nHe highlighted the strong grade improvements and high zinc recovery as encouraging indicators that XRT sorting could form part of the project’s future processing strategy.\n\n**The next stage will involve a substantially larger bulk sample for testing under more representative commercial conditions**, with Rockfire indicating that suitable material may be sourced from underground workings once access is restored.\n\nThe company intends to incorporate the potential ore sorting circuit into the processing flowsheet being evaluated for the forthcoming feasibility study.\n\n**Capital and operating costs associated with installing and running the sorting equipment will be assessed**, alongside its potential impact on downstream processing performance and overall project economics.\n\nAlthough the laboratory results are encouraging, **the test involved a relatively small sample and only the selected particle-size fraction was sorted**.\n\nFurther work will be required to establish how the technology performs across representative ore types, including variations in mineralogy, particle size and zinc grade.\n\nThe reported **97.7% zinc recovery relates specifically to the ore sorting tests**, not the overall metallurgical recovery that could ultimately be achieved from a commercial processing plant.\n\nRockfire also confirmed that **its maiden JORC-compliant germanium Mineral Resource Estimate is nearing completion**, providing another potential development milestone for Molaoi.\n\nGermanium is a strategically important material used in specialist electronics, optical systems and other advanced technologies, potentially adding to the project’s critical minerals significance.\n\n**For Rockfire, the successful preliminary sorting tests represent a step towards optimising the Molaoi processing strategy**, with the possibility of increasing feed grades while reducing the volume of material requiring further treatment.\n\nThe immediate priorities will be **larger-scale TOMRA testing, completion of the germanium resource estimate and further development of the processing flowsheet**.\n\n**The 132.5% zinc grade uplift provides encouraging technical evidence, but commercial-scale testing and detailed feasibility work will be necessary before its economic benefits can be established.**"}