How Diatreme’s Northern Silica Project Achieved Solar-Grade Silica Sand Breakthrough
Diatreme Resources confirms its Northern Silica Project can produce low-iron, high-purity silica sand meeting photovoltaic glass standards, backed by successful bulk metallurgical testwork. The results pave the way for final engineering and commercial deals amid a booming solar energy market.
- Bulk testwork achieves 85.6% product yield with low iron impurities
- Silica sand meets stringent photovoltaic glass specifications
- Magnetic separation optimization offers further impurity reduction
- Northern Silica Project awarded Major Project Status by Australian government
- Plans underway for larger-scale trials and final feasibility studies
Confirming Product Quality at Scale
Diatreme Resources Limited (ASX, DRX) has announced compelling metallurgical testwork results from its Northern Silica Project (NSP) in Far North Queensland, confirming the project’s ability to produce high-purity, low-iron silica sand suitable for photovoltaic (PV) glass manufacture. This milestone validates the transition from earlier benchtop trials to bulk production, with an impressive 85.6% product yield and iron oxide levels consistently below 130 parts per million (ppm), aligning closely with industry standards.
The bulk sample, sourced from a carefully selected area within the Si2 Mineral Resource, underwent a conventional wet processing flowsheet including gravity separation, attrition scrubbing, classification, and magnetic separation. Notably, the spiral circuit stage achieved a 91.9% recovery while significantly reducing iron content, a critical factor for PV glass quality.
Magnetic Separation and Product Refinement
Further testwork explored advanced magnetic separation techniques, including induced roll magnetic separators and electrostatic separation, which demonstrated potential to reduce iron impurities to as low as 86 ppm without compromising yield. Collaborations with Chinese magnetics supplier Shandong Huate Magnet Technology revealed that alternative magnetic circuits could streamline processing or enhance product purity, offering flexibility in final plant design.
These findings are significant given the stringent requirements of the photovoltaic glass market, where iron impurities can affect glass clarity and performance. The NSP’s product meets or closely approaches Chinese national standards for PV glass, underscoring its commercial viability.
Strategic Importance and Next Steps
The Australian Federal Government’s designation of the NSP as a Major Project highlights its strategic role in the country’s critical minerals and renewable energy ambitions. Situated near established silica sand operations and export infrastructure, the NSP is well positioned to supply the growing global solar energy market.
Diatreme plans to advance with spatial variability testing across the deposit to ensure consistent product quality, followed by larger-scale bulk processing trials. These steps will inform final process engineering, capital expenditure estimates, and underpin negotiations for binding offtake agreements ahead of the Final Investment Decision.
With a global silica sand resource exceeding 500 million tonnes and strong backing from development partner Sibelco, Diatreme is poised to contribute meaningfully to decarbonisation efforts by supplying premium silica for solar PV glass.
Bottom Line?
As Diatreme advances toward feasibility and commercialisation, the Northern Silica Project stands as a promising supplier in the solar energy supply chain, but upcoming large-scale trials will be critical to confirm consistent quality and process efficiency.
Questions in the middle?
- How will spatial variability across the NSP deposit impact final product consistency?
- What are the timelines and terms expected for binding offtake agreements with glass manufacturers?
- Could alternative magnetic separation technologies reduce capital costs or improve margins?
