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Hammer hits ore sorting success at Kalman - The Pick Online Magazine

Written by Staff Writer | Nov 2, 2022 2:57:16 PM

Hammer Metals Ltd (ASX: HMX) has achieved positive preliminary ore sorting test-work has been completed on samples taken from the Kalman Cu-Au-Mo-Re deposit, located 60km south-east of Mt Isa in North-West Queensland.

The test work was conducted by Steinert at its Bibra Lake facility utilising a combination of 3D laser and X-Ray sensors to differentiate inputs into waste and those matching parameters of target elements. These two sensors were utilised to tailor an optimum combination for specific mineralisation mineralogy.

The aim of this trial test work was to determine whether ore sorting technology could be applied to ore from the Kalman Deposit. The favourable initial results give Hammer confidence to embark on a larger program of testwork.

Location of samples

Samples were taken from K-23A and consisted of half core. Four samples, representing distinct ore zones, were taken based on whether ore was dominantly copper or molybdenum rich. Overall, these samples, when combined, provided a representative sample of Kalman’s copper, gold, molybdenum and rhenium resource grades.

This is a tremendous result from early-stage test work and shows that the Kalman deposit is amenable to ore sorting technology,” Managing Director, Daniel Thomas, said.

“Processing costs can represent a significant proportion (>50%) of overall production costs and reducing the amount of sub-economic material going through a grinding and flotation circuit could significantly increase project returns. Similarly, an increased head grade through the grinding/flotation circuit may lead to significant capital savings by reducing the required throughput capacity of the plant.

“It was pleasing to see the copper and molybdenum ore domains both behave in a similar manner to the same sort algorithm. The overall benefits of ore sorting will not only apply to reduced operating and capital costs, but are also likely to result in an expanded resource when the upgrade factors are applied within the Kalman Resource model.

“It’s an exciting time for the Kalman Project as we embark on further shallow extensional drilling. Successful drilling and learnings from the ore sorting test work will enable Hammer to review and upgrade the existing resource model.”

Process and results

These samples were transported to Western Australia and crushed to 10-31.5mm. Before combining the samples, each sample was scanned separately using the combination sensor sorter, taking measurements from all four sensors. The scan data was used to develop a bespoke combination of XRT and 3D-laser sort programme.

Given the similarity in the nature of the copper ore and each response to the initial scan, samples KMET01- KMET03, were combined. It was decided that KMET04, which was molybdenum-rich, was processed separately.

Steinert ran the material through the ore sorting test rig in multiple passes to examine the sensitivity of Kalman ore to various settings. Multiple passes of each sample were conducted to examine mass reduction and beneficiation.

Pleasingly, utilising the same sorting program, the behaviour of the two separate samples, KMET01-03 and KMET04 was similar, indicating the suitability of the ore sorting technology to be applied across the Kalman deposit.

The results indicate that >80% of the combined value of the ore can be recovered with a 40-45% reduction in mass processed. Specifically, the ore sorting setting of rejecting low density material could achieve:

  • Copper grade increase of 28% (0.71% to 0.91% Cu) with a mass reduction of 35% and recovery of 83.4%;
  • Gold grade increase of 39% (0.23g/t to 0.32g/t Au) with a mass reduction of 35% and recovery of 90.7% %; and
  • Molybdenum grade increase of 103% (0.33% to 0.67%Mo) with a mass reduction of 61.8% and a recovery of 76.6%.

The initial work indicates that the Kalman deposit is very amenable to ore sorting and that bulk testwork should be undertaken.

Next Steps

Hammer is reviewing the initial ore sorting testwork results and identifying zones within the Kalman Deposit which could be utilised in a more expansive programme. Hammer is also reviewing these results in the context of potential changes in resource modelling in combination with potential scale decisions for a future scoping study on the project.

A review of the resource model is likely to be considered post the completion of the upcoming extensional drilling programme. For further information please visit: https://hammermetals.com.au/