For reference..
Quote:
you can make a 'magic key' with tinkering and magery.
takes 5 silver ingots 5 gold ingots and 5 copper ingots....
This appears to be a bug. "Magic Keys" in the old Ultima series and the original Ultima Online were meant to open "magical doors". Magical Doors are typically blocking things like treasure room entrances in the old Ultima games and quest rooms in UO.
You have confirmed copper ore doesn't seem to be accessible at all, which I'm pretty sure it should not be. The magic key should be removed from the crafting menu.