Perpetual Resources Ltd (ASX:PEC) has completed a stage three, 86-hole aircore white sand drilling program at Beharra high-grade silica sand project in Western Australia, a key step in informing a development decision for the project.
The aim of the program was to provide certainty on the first 10 years of mine life at Beharra under a premium white sand only mining and processing scenario, as compared to the previous development scenario, which included processing of the less pure yellow sand sequences as well.
Drill samples are being prepared for shipment to Intertek, which will undertake testing for reporting of exploration drill results.
“Emerging silica sand export industry”
The results of this drill program are expected to inform the development pathway at Beharra.
Perpetual managing director Robert Benussi said: “The conclusion of this aircore program, which saw the successful completion of 86 aircore holes, is potentially a pivotal step in our understanding of the Beharra project, with the results expected to inform whether a white sand only development scenario is optimal for the project.
“Pleasingly, while drilling, we encountered primarily thicker than expected white sand intersections, which bodes well for potential reserve estimate and subsequent study outcomes.
“The visible and extensive white sands encountered during this drill program also provide further validation of our previous belief, that Beharra is shaping up to be the leading Mid-West silica sand project and a potential key player in the emerging silica sand export industry for Western Australia.”
IHC metallurgical testing
Additionally, samples will also be sent to specialist sand testing laboratory IHC Robbins in Brisbane, who will undertake metallurgical testing on a 2-tonne representative bulk sample generated from the drill sampling.
The purpose of the IHC Robbins bulk testing program is to determine impurity levels from a wider white sand composite sample (as opposed to the initial 300-kilogram sample from two shallower locations).
IHC Robbins will look to define a flow sheet that is replicable under a full production scenario, noting that the results announced on 22nd April 2021 utilised laboratory equipment only and not full production equipment.
Based on current timelines, results from this testing program are due in the third quarter of 2021.
Results of this white sand only drill program will be utilised in planning for the Beharra updated pre-feasibility study as well as the subsequent feasibility study, with updated timing to be provided once results are known.
Silica sand market
The drilling program is aimed at replicating the previously announced 300-kilogram white sand only laboratory tests which demonstrated that Beharra white sand could be upgraded, using only gravity and magnetic separation process methods, to 99.8% silicon dioxide (SiO2) and iron oxide (Fe2O3) content of 120 parts per million.
This earlier result was seen as exceptional and suggests that Beharra white sand could be suitable for the higher-priced and fast-growing solar PV-cell manufacturing industry, which requires low Fe2O3 silica sand.
Uses for silica sands of increasing purity (>99.5% SiO2) includes glass making, with uses for purity >99.8% includes semi-conductor fillers, LCD screens, and optical glass.