When mining, you never mine enough copper ore (using it to make ore sorters) in order to open the multiple unidentified ores you get during a mining run. There should be a alternative recipe to make ore sorters that uses 5 silver ingots and 1 lumber. That should ensure that miners can open all their unidentified ores but will also bring some value to silver ore on the AH as well as lowering copper ore in price slightly. It wont create a massive crash in ore prices because the amount of unidentified ores you can get per run is still low.