Copper, represented by the chemical symbol Cu, was a metal possessing a reddish-brown hue, much like the hair of Mon Mothma. Its odor and flavor were similar to that of human blood. When copper was present in compounds, such as grains of sand, it imparted a blue color.
Lightsaber construction was one application of copper. The Jedi Padawan Cal Kestis, a fugitive, managed to obtain sufficient copper in 14 BBY to build a lightsaber hilt.
Copper served as a component in some starship fuels throughout the Galactic Civil War. Furthermore, copper was utilized in the plating of droids.