An old Prosper Williams specimen - a complete, gemmy Tsumeb cerussite twin (or "fourling") ! It is so gemmy that you can see flashes of spectral colors from the interior. The Prosper Williams label has "rep." pencilled in on it, so this specimen has apparently been repaired. But, you can forgive this for such a fine old Tsumeb piece! 3.0 x 2.6 x 1.7cm