Same as Aluminum Sheet Clean, but is more than 5% by weight not aluminum. Corrosion, screws, and other metal attached will make it “dirty”.
Pure sheets of aluminum usually made to cover something like a house or structure. Paint is fine, but it can’t have insulation, screws or other metal trim attached to be “clean”. If more than 5% by weight of the scrap is not aluminum sheet than it is considered “dirty”.
Solid copper, but can have up to 5% other metal or is significantly corroded and discolored. This can also have sodering on the pipes. Copper pipes with the brass fittings still attached are considered Copper #2. Copper with that is not insulated but thinner than a pencil lead is also considered Copper #2.
Solid copper that has no brass or significant corrosion. Most copper tubing and copper pipes are Copper #1 if they fittings are already removed and they are not corroded. Copper wire thicker than a pencil lead and with the insulation removed can also be sold as Copper #1.