New scrappin nut in South Carolina

I need to learn to see the different types of aluminum. The copper is pretty simple, and I'm hoping the brass is too.

http://cedarcityrecycling.com/aluminum/
Study this link and all different types of nonferrous metals (magnet won't stick). My yard only pays on 3 or 4 different types of alum. They kind of lump some of it together. They may sort it in-house, I don't know. The link will also show you different brass and coppers types and styles.
The yards categorizes differently and they all pay differently. Different parts of the country affects the prices also.