Bronzium
this metal was quite dense, and was often used in the creation of structures where radiation might be a threat. One of its most prominent uses was in the case-hardened bulbs which held the reactor core of the Trade Federation's droidekas. It also found use in the creation of cast sculptures and busts. Even C-3PO was plated in bronzium, after the droid was given to Padme' Amidala as a gift from her husband, Anakin Skywalker.