Superconductors (niobium-tin rods or wires in copper) are very rare, hard to come by, and expensive metals that conduct electricity or transport electrons from one atom to another and have no resistance. Superconductors are used to make extremely powerful electromagnets that accelerate charged particles very fast (close to the speed of light). This is a special kind of metal, the black area is usually an alloy of titanium and niobium, and the surrounding area (red) is copper, a new super material! Super rare, super hard to use and super expensive. Perfect for collecting.