Great Dirt Resources (ASX: GR8) has confirmed multiple zones of high-grade manganese oxide mineralisation at its Basin and Neranghi projects in northern New South Wales, with rock chip assays returning up to 51.8% manganese.
The results, which came from selective sampling of historical workings and outcrops within Great Dirt’s exploration licence EL9527, validate the company’s geological model for potential manganese at depth.
Great Dirt said the findings support its broader research program focused on identifying previously unrecognised primary manganese systems across the Doherty and Basin projects.
High-Grade Mineralisation Confirmed
Rock-chip sampling across both Basin and Neranghi identified massive manganese mineralisation in boulders and outcrop up to 70 centimetres in size.
Samples from the Basin (Copper Hill) area returned manganese grades ranging from 22.6% to 51.8%, with notable results including 50.5% and 51.8% from Copper Hill, and 45.1% and 51.8% from Neranghi.
These results build on previous discoveries at the Doherty project, where earlier sampling returned grades up to 50.3% Mn.
Great Dirt noted that its current sampling approach aims to map extensions of high-grade material and define structural controls to guide deeper exploration.
Advancing Research and 3D Modelling
The company is continuing its comprehensive research initiative with specialist consultants to assess the potential for primary manganese oxide systems beneath known workings.
The program integrates geochemical, geophysical and structural datasets, with advanced processing and the proprietary 3D modelling techniques Eureka Consulting and consultant geophysicist Peter Gidley have developed to enhance the resolution of magnetic, gravity, and induced polarisation data.
This allows for refined targeting of subsurface mineralisation.
Initial results from the modelling have identified and ranked several key target areas for further ground investigation, with field work during the next phase to collect additional samples and data for testing.
The company expects to release the detailed research outcomes once analysis is complete and it has been able validate the priority targets.
Strong Historical Production
Great Dirt’s Doherty and Basin projects have a strong production history, with mining from 1941 to the early 1960s yielding about 9,000 tonnes of battery- and metallurgical-grade manganese.
The company believes previous operators focused primarily on surface enrichment zones, leaving potential blind deposits untested, and plans to undertake systematic geophysical and geochemical surveys to identify extensions and new mineralised zones suitable for modern development.
In addition to its NSW assets, Great Dirt has expanded its exploration footprint with the acquisition of two tenements near the Woodie Woodie manganese mine in Western Australia, as well as a new lithium-prospective project 43 kilometres from Pilbara Minerals’ (ASX: PLS) Pilgangoora operation.
The company believes its growing manganese portfolio positions it to participate in future supply chains for both steelmaking and battery-grade manganese products.
