parts of furnace to scrap

what are some very valuable parts in a furnace to scrap ? , i have one coming to me soon. thanks guys

Little of everything in there...brass, copper, aluminum maybe, steel. Take it apart and separate.
http://www.google.com/imgres?imgurl=...QEwAQ&dur=2168

thanks for that link KZ, I'm actually scrapping out the old gas furnace in my dads garage I work out of as it hasnt been hooked up in years so its nice to know what the internals look like.

I've found that a lot of furnaces have a large copper coil in them. On the outside look for a metal circle about 10 or so inches across with copper outlets on it. Remove all the bolts, I torch them out personally, and the copper coil will pull right out. I sell these as #1 copper. Note: not all furnaces have such coils.