I've noticed that many metallic items that look silver-ish in color, attain that effect because of a thin surface coating. Whenever those items get scratched, a copper-colored metal is revealed to be the bulk of the material. What is this cheaper metal? Copper is quite expensive so I doubt that's what it is...

[![example](https://i.stack.imgur.com/7HGdJ.jpg)](https://i.stack.imgur.com/7HGdJ.jpg)