[Source] Trimantium was a gray-green metal which could be used to make armor plating for starships. The HT-2200 medium freighter model of ship, which was made by the starship manufacturer Corellian Engineering Corporation, had trimantium plating lining the hull, giving the ship unusually high tensile strength. The protocol droid C-D20 mentioned that feature when describing the model to a Rebel looking for a freighter to use for his next mission. The metal was also used in the creation of weapons and armor during the Galactic War between the Galactic Republic and the Sith Empire.