T325.  I believe this to be san mai awase construction: thin plates of either shakudo or yamagane with a core of copper.  The fukurin is shakudo.  I’m not 100% certain about the construction because usually with san mai you can see separation between the elements; with this one everything is tight together.  However it was made, the pastoral scene of birds, deer, and trees is the same on both sides and condition is excellent.  6.3 x 6.3 x .4 cm.  The nakago hitsu-ana is .7 x 2.4 cm.  $150.