Just a black and white akro cork with metallic? It appears to be tinged blue at the edges, but I wonder if that is just the black thinning out over the white. Tx.
Yeah, some of them are black looking until you see the edges where the black thins over the white and then it turns out to be brown, blue, or purple. You don't see metal on Akros very often. Yours looks like contamination maybe, hard to tell but it doesn't follow the glass, more like it came off the rollers maybe.