Pan Asia’s ore sorting testwork has highlighted the excellent amendability of Reung Kiet lithium mineralisation to this low-cost method of increasing mill grade.
Crushed drill core samples from the project in southern Thailand demonstrated exceptional recovery of separate highgrade dyke and vein material from lower grade/waste siltstone after undergoing 3D laser and colour sorting at Steinert Australia.
Pan Asia Metals (ASX:PAM) noted that the results indicate about 73% lithium recovery while discarding 61% of the feed, which is generally waste siltstone with grades well below the resource cut-off grade of 0.25% Li2O.
The reduction of mass by 61% and the near doubling of lithium grade from 0.48% Li2O to approximately 0.9% Li2O is expected to deliver substantial processing cost savings.
Increasing mill feed grade
Managing director Paul Lock noted that the company had considered ore sorting as a way to increase mill feed grade back in June 2022 when it released its maiden resource for Reung Kiet.
“Steinhart Australia’s ore sorting test-work has demonstrated the ability to uplift the head grade to the beneficiation plant, in this case almost doubling the grade to >0.90% Li2O, which means that we would be processing a higher grade ore than that reflected in our MRE,” he added.
“This is a fantastic outcome and we expect it will result in capital and operating cost savings as we will require less beneficiation capacity – lower capex – and we will be processing less product – lower opex.”
Ore Sorting
The crushed drill sample, which demonstrated good physical separation of purple-white pegmatite from the dark grey to black coloured siltstone, fed in a single-pass into Steinhart’s ore sorted and subjected to 3D laser scanning and colour camera sensors used in combination.
This produced excellent separation of the mineralised aplo-pegmatite from the low grade to waste siltstone.
Data from the sorted ore found that -50mm, +10mm pegmatite and mixed -10mm fines samples constitute about 39% of the sample yield and contain around 73% of the contained lithium.
Meanwhile, the siltstone sample constitutes about 61% of sample yield but only 27% of contained lithium, and almost all of this is below the Mineral Resource cut-off grade of 0.25% Li2O and hence is not really a loss.
The results clearly demonstrates that the sampled mineralisation is highly amenable to ore sorting which results in the separation of the material into essentially homogeneous aplo-pegmatite with little siltstone contamination and siltstone with little pegmatite.
This article was developed in collaboration with Pan Asia Metals, a Stockhead advertiser at the time of publishing.
This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.