I wish you wouldn't bring that up !! I was turning all mine in as copper cause I did not know that some were Au......UNTIL YOU TOLD ME !!! Now, my conscience won't let me !! AND, after you EDUCATED me I started finding twice as much AU ones....you jinxed me also !!
I thought you would have seen that in my original post called "breaking down a monitor" back in the summer (I didn't rate a sticky) You can tell if you pick one of them alum. ones up in one hand and a copper one in the other, weighs half as much. and can be about any color. Just clip a few strands to know for sure.