Coaxial Cable looks like copper but in reality the Coaxial Cable is just steel wire that has a bit of copper coating on it.
The Shield around the steel wire on the Coax I believe is aluminum but it could be made of something else and there's really no value in scrap for Coaxial Cable unless you can put it inside something such as a refrigerator etch to take it to the scrap yard.
I tried selling some Coaxial Cable to the scrap yard before and they said they didn't buy it and didn't know of anyone else that would buy it since it didn't have much if any value.