COPPER, COPPER ALLOY, COPPER SCRAP
Copper (Cu) - reddish, extremely ductile metal that is an unusually good conductor of electricity and heat. Copper is found in the free metallic state in nature. This native copper was first used (c. 8000 BCE) as a substitute for stone by Neolithic (New Stone Age) humans. The pure metal is second only to silver in thermal and electrical conductivity.
ALUMINUM, ALUMINUM ALLOY, ALUMINUM SCRAP
Aluminum (Al) - lightweight, silvery-white metal. Aluminum is the most abundant metallic element in Earth’s crust and the most widely used nonferrous metal. Because of its chemical activity, aluminum never occurs in the metallic form in nature, but its compounds are present to a greater or lesser extent in almost all rocks, vegetation, and animals. The metal and its alloys are used extensively for aircraft construction, building materials, consumer durables (refrigerators, air conditioners, cooking utensils), electrical conductors, and chemical and food-processing equipment. Aluminum is an excellent conductor of heat and electricity. Its thermal conductivity is about one-half that of copper; its electrical conductivity, about two-thirds. All natural aluminum is the stable isotope aluminum-27.