It looked like copper plating to me but that brings up another question. Copper over Aluminum is not a good combination from what I remember. Al has an expansion coefficient twice that of copper. This means as temperature extremes come into play the Al is going to want to expand or contract more than the CU can. That can lead to some interesting delamination if they were put into practical use. Also CU corrodes green and does it rather quickly, my guess is that if this is really copper then they have to clear coat it and that is another issue. Now I have not looked at a galvanic chart for some time so I cannot speak to the galvanic reaction that might be present in moist conditions. Either way, these are probably best shown where they are, in a box. To use them, even for casual rides will become a maintenance nightmare but then again, I do believe this groups loves to rub metal. Yeeeessss!
Ray Homiski
Elizabeth, NJ