Radius geologists in January 2020 re-discovered an undocumented large scale underground bulk silver mining operation where in its estimated in the late 1800’s, historic silver miners hand excavated an extensive series of anastomosing caverns, producing silver bars at an associated smelter operation. The project is located in remote part of the Sierra Madre gold and silver mine belt and appears to be un-explored since the miners ceased their operations. No references to the project have been found within the Mexican Geological Survey or any literature. The few local residents have no knowledge of exploration companies working in the area and there are no indications of prior exploration within the silver mines or surrounding outcrops. There was a pre-existing mineral concession covering the area, but the owners of the concession had never visited the property and were happy to option the property to Radius.