All materials are priced based on how the materials are. The cleaner the material, the more value it has. It is worth your time to sort the materials to get the maximum payment for your materials. Copper is separated into five general categories: Bright & Shiny (B&S) Copper Wire, Copper #1, Copper #2, Copper #3, and Copper Wires (different % pays different price).
Bright & Shiny (B&S) Copper Wire is the most expensive of the copper category. It is basically bare copper wiring without any plastics or tape.
Copper #1 are clean copper piping or sheets that have no solder, paint, green oxidation, or other materials attached to it.
Copper #2 are copper piping or sheets that have solder, paint, green oxidation, and very small amounts of other materials attached to it.
Copper #3 are copper piping or sheets that have other materials (brass, ferrous metal, plastic, or tar) attached to it.
Insulated Copper Wire are copper wiring that still have plastic or aluminum wrapping. Separate the copper wiring based on estimated percentage of copper for best pricing. In general, wires with single insulation pays more than double insulation.