Exceptional Metallurgical Test Results Obtained At Silica Sands Project
Perpetual Resources Limited (ASX: PEC) has reported “exceptional” results from a 2,000kg bulk sample metallurgical testing programme from material obtained from its Beharra silica sand project in the Mid-West Region of Western Australia.
Silica sands have an extensive range of uses including lower purity and grade applications such as construction sand, proppant sand used in oil well fracturing, and foundry sand. With increasing purity (>99.5% SiO2) uses includes glass making including clear glass. Uses for purity >99.8% includes semi-conductor fillers, LCD screens, and optical glass.
Managing Director, Robert Benussi, said the latest tests have highlighted the potential to process high-grade material at Beharra.
“These results demonstrate that, based on publicly available information, the Beharra silica sand project can produce a high- quality final silica sand product in the Mid-West Region of Western Australia.
“The comprehensive metallurgical test work programme was executed using full size commercial or genuinely scalable equipment. This provided a genuine representation of a production scenario where the run-of-mine feed at Beharra is a mix of white and yellow sand intervals.
“We are currently testing a workflow that may demonstrate further product optimisation via the processing of selectively mined white sand horizons. These results also provide a strong catalyst to further advance our existing and potential future offtake negotiations.
“To have achieved impurity levels for our lowest impurity product that are, based on publicly available information, significantly lower than the levels of those of nearby deposits, clearly demonstrates the superior quality of the Beharra project and bodes well for the market’s acceptance of the higher quality Beharra product.
“As we rapidly close in on the delivery of the Beharra PFS our confidence in the bankability of Beharra continues to increase.”
The latest 2,000kg bulk sample testing programme, undertaken by renowned mineral sands testing business IHC Robbins (IHC) at its laboratory in Brisbane, emulated results that can be expected using the run of mine material in relation to the process recoveries and expected product qualities.
The bulk sample comprised of sand samples from each 1.0m interval from all air-core holes, drilled in March 2020 to the south of Mt Adams Road, in the area which falls within last year’s announced Mineral Resource.
The bulk sample was composed of approximately 10% yellow sand and 90% white sand, with the samples selected based on a lower grade cut-off of 98% SiO2, to a maximum depth of 10m, being above the water table.
The test programme was designed this way to properly mimic a simplified mining and production scenario and provides the highest confidence yet that results will be repeatable at Beharra for the life of mine operation.
Another key focus of the bulk testing program was to aid in flow sheet design as part of the soon to be delivered Pre-Feasibility Study (PFS) and also to provide potential end users with confirmation of what product quality they could likely expect without the application of any selective mining of processing strategies.
Mr Benussi said the programme has also therefore delivered a large quantity of product samples that will be utilised for continued sales and marketing efforts.
Throughout the developed process, a potential primary product was generated, referred to as ‘Beharra Premium’.
Beharra Premium then had the option of being classified over a 600μm screen to produce a coarse product and a fine product, referred to as ‘Beharra Special #27’ and ‘Beharra Special #46’, respectively.
The outcomes of this metallurgical programme have now allowed the development of detailed product specification and technical sheets for currently proven multiple end products. The Beharra project has so far shown it can potentially deliver three discrete product streams to the Asian markets, with the key differentiator being Fe2O3 impurity levels, and secondarily Al2O3 impurity levels.
After completion of the PFS in February 2021, Perpetual will continue to undertake detailed trade off studies with a view to optimise the ultimate output from Beharra to maximise the average revenue per ton that can be achieved.
Perpetual considers the end product outcomes already delineated to be highly supportive of Beharra emerging as an important high grade silica sand project and a pre-eminent project in the Mid-West Region of WA.
Mr Benussi said Perpetual move forward to engaging more deeply with potential customers in its sales and marketing activities in the months ahead, with a strong focus on Asian demand.