红铜

红 = 工 + 纟 : Mnemonic symbol: a little red book.

Helga Horse (hu) is reading the little red book (红) in the engine's kitchen ((e)ng2), when she discovers that it is being eaten by a silk worm (纟). She overreacts a little and wants to beat the silk worm with a steel beam (工).

铜 = 同 + 钅 : Tommy Turtle (tu) runs a copper (铜) mine in the engine's kitchen ((e)ng2). He managed to force two twins (同) to work for him and mine the copper using golden harpoons (钅).