Copper


 * For the individual, see Bayldon Copper.

Copper was a metallic element. When oxidised, it would turn green in a process called verdigris. (PDA: Verdigris)

When the Timewyrm possessed Dumuzi, she had him place copper around the walls of Kish, turning it into a giant radio transmitter. (NA: Timewyrm: Genesys)

Copper was used in the casings of many Earth bullets. When the Sontarans invaded in 2009, they used Cordolaine signals to excite the copper, causing bullets to stick in the barrel. (DW: The Sontaran Stratagem/The Poison Sky)

Kaleds had copper in their blood, giving it a green colour. (BFA: Corruption)