It may be one of those dipped until the brass dissolves ones. I think the reason it's darker in color is because it is base metal and not silver. I think there is a chemical that can be put on metals to test them, but have no clue about that. I'm sure a coin store would have info.

I have seen dipped strikes and the rims get less gold color and more silver color. I will take a really old and messed up strike and go buy some EZest and dip the heck out if it and see what it produces. My guess is I will end up with a "silver" looking rim. I'll try it and post pics what it looks like.

Jeff Bitzer, why don't you put an end to this and get the info from the mint, can't your club coin contact assist you? Ask him how the hell the strike blanks are made. Ralph, how about you, as President of the club, can't you contact the mint to get the official composition of a strike for the club's information?