Electical Wire Salvage

Hello, I do very small amounts of scrapping. Mostly saving copper from wire that is destined for the trash. A few times while stripping the wire I come across silver looking wire instead of the copper I want/expect. Sometimes it is on the outside of the inner casing of rubber after stripping off the most outer layer of rubber. What is this metal? Is it worth keeping? Thanks!

Welcome to the Forum. Your "silver-looking" wire is aluminum. Not worth as much - you'll probably get 0.57 to 0.75/lb, depending on where you are. You'll have to decide if it's worth it. It takes a lot of aluminum to make a pound. Learn the difference between sheet, cast and extrusion aluminum.