U.S. Bureau of Mines research is providing new insights into predicting in situ mining metal recoveries. Potential problems and constraints are being identified and modeled before field leach mining tests are initiated. As part of this research, the Bureau is conducting a geologic characterization study of the drill core from the Cuyuna Range and Emily District, which includes stratigraphy, gangue and ore mineralogy, textural relationships, assays, detailed whole-rock chemical analyses of selected samples, permeability and porosity, fracture analysis, and magnetic susceptibility. A combination of laboratory geologic characterization techniques are being used on whole-core samples to determine ore-gangue and structural relationships of preleach and postleach material. These techniques include petrographic analysis of polished thin sections, scanning electron microscope imaging, electron microprobe analyses, and x-ray diffraction.
Paper in Proceedings, Inst. on Lake Superior Geology, V. 37, Pt. 1, PP. 26-28