Beachcombing Mystery

While collecting puka shells ("puka" is the Hawaiian word for "hole" hence a piece of shell with a natural hole in it used for stringing necklaces, bracelets, etc.) on Sunset Beach (North Shore Oahu) I came across these little pieces of battered aluminum. I have speculated that they are the remains of aluminum cans, beach chair frames, etc. If you have ever found stuff like it please let me know. If you have a theory of your own as to where it comes from, let me know that, too.

In any case, they look almost exactly like gold nuggest....minus the gold!