Image source: Shutterstock

Highlights:

  • SUM shares jumped 22.58% to AUD 0.038 on 25 June 2025 following metallurgical test results.
  • Test work confirmed high-grade tantalum and niobium amenable to simple density-based separation.
  • Second round of sampling planned to refine processing methods and enhance recoveries.

Summit Minerals Limited (ASX: SUM) saw its share price rise 22.58% to AUD 0.038 on 25 June 2025 after announcing promising metallurgical results from its Equador Project located in Brazil’s Paraíba and Rio Grande do Norte states. The company is investigating the project for tantalum (Ta) and niobium (Nb) potential, with early-stage results indicating the materials can be effectively concentrated using conventional separation techniques.

The recent test work, conducted by Independent Metallurgical Operations Ltd (IMO), focused on three previously identified samples SUMMET 8, 9 and 10. These samples were selected due to their elevated head assay values for tantalum, as confirmed by earlier bulk sampling. IMO applied two density-based methods: Heavy Liquid Separation (HLS) and Gravity (Wifley) Table separation.

Both testing methods showed that the mineralised pegmatite material is amenable to beneficiation using simple density separation techniques. These findings provide technical support for developing a straightforward processing flowsheet tailored to the physical and chemical properties of the mineralised material at Equador.

The HLS analysis yielded tantalum grade uplifts ranging from 43 to 56 times the original concentrations and niobium uplifts between 30 and 41 times. While the Wifley table method produced more moderate upgrades (2–7 times for tantalum and 5–7 times for niobium), the test conditions were generic. IMO suggested that more targeted adjustments to table settings could improve these outcomes.

Further analysis also indicated that previous head assay results from SUMMET 8 and 9 may have underreported the concentration of tantalum and niobium due to the coarse grain size of mineral-bearing particles. The recent tests, which included size fraction analysis and HLS, revealed higher concentrations in larger particles information that will inform future crush size and separation density parameters.

Sample preparation involved coarse crushing to below 3.35 mm, followed by sub-sampling for various tests. The gravity separation work was performed on -1,000 + 53 µm material, and the +1,000 µm fraction where the highest concentrations were observed in HLS was not evaluated via the Wifley table due to grain size limitations. IMO has recommended testing spiral separation on the coarse material to fill this gap.

In the next phase, Summit plans to collect a second round of bulk samples from the same zones where SUMMET 8, 9, and 10 were initially obtained. These will undergo detailed mineralogical analysis to refine the specific gravity threshold for HLS and to better understand grain size distribution across mineralised zones. This will support optimisation studies for processing design, including crush size selection and separation method calibration.

In parallel, Summit continues its regional soil sampling program across the Equador project area, focusing on what it describes as a “fractionated pegmatite corridor.” The first batch of soil samples has been shipped to Intertek Laboratories in Western Australia for multi-element analysis. The program will expand to the Barra and Juazerinho areas as it progresses.

Summit Minerals Limited is an ASX-listed exploration company focused on battery minerals, with projects targeting high-demand commodities. The company aims to define JORC-compliant resources through systematic exploration and technical evaluation.