How do you say copper in English?

Look at you. What kind of copper do you want to express?

Copper refers to pure copper.

Bronze means bronze: the police are called cop, which is equivalent to "police" in Chinese. In fact, the word cop is the abbreviation of copper, because in the past, police uniforms used copper buttons, so people used copper to refer to the police.

Brass refers to brass; A brass musical instrument can be brass, because it is made of brass.