Pioneer Minerals (ASX:PMM) has reported a major geophysical breakthrough at its Springfield Prospect in Idaho, with new airborne magnetic data from an independent geophysical interpretation showing a large anomaly stretching 2.9km long and 600m wide, far larger than the historic mine footprint.
Independent studies confirm tungsten occurs as scheelite closely linked with pyrrhotite. Because pyrrhotite is magnetic, it explains the anomaly and serves as a reliable proxy for tungsten. Rock chip samples returned grates up to 2.98% tungsten trioxide.
The company notes that Springfield now shows strong similarities to the Dolphin tungsten skarn in Tasmania.
Other prospects in the North Pine Project are now of interest to Pioneer. At Silver Cliffs, folded metasedimentary units and magnetic features remain unsampled. At Northman, granite-metasediment contacts are considered highly prospective for skarn-style mineralisation.
CEO Michael Beven says that the study results provide strong evidence that the historical interpretation of an isolated tungsten skarn actually is part of a much larger, previously unrecognised mineral system.
“The clear spatial and genetic link between scheelite mineralisation, pyrrhotite-dominant sulphides, and the magnetic anomaly fundamentally changes our understanding of the Springfield system,” Beven says.
“Rather than targeting isolated surface occurrences, we now have a coherent, district-scale framework to guide exploration.”
The company has staked 223 lode claims at North Pine, though tenure is still awaiting confirmation by the Bureau of Land Management. Springfield is now a priority target for Pioneer’s US critical minerals portfolio.
Pioneer Minerals is a North American critical minerals explorer, advancing a portfolio of tungsten, antimony, uranium, and lithium projects.
Write to Amy Rotman at Mining.com.au
Images: Pioneer Minerals
