T422.  Copper or yamagane tsuba.  7.3 x 7.6 x .4 cm.  The nakago hitsu-ana is .8 x 2.9 cm.  A crab worked in shakudo sits on a leaf worked in gold and shakudo; on the back water is represented with shakudo streams.  Late Edo or maybe even later, I believe (but what do I know).  Condition is excellent.  $175.