The small rocky reef at the tip of the Sibley Peninsula in northwestern Ontario, Canada, is rich in silver, but mining this precious metal is a nightmare. Much of the silver is located below the surface of Lake Superior, and anybody who has ever lived on the shores of this great lake knows that it is incredibly unpredictable and extremely dangerous. Extracting silver from beneath the lake would require building a wall to keep water away and pumps would have to be kept running continuously to clear water that would constantly collect at the bottom of the mine shaft.

Silver Islet in 1911. Photo: James Fraser Paige/Wikimedia Commons