This sweet little powder box is made of brushed metal.  It originally had a powder puff inside and would have been a cherished gift for the lady of the house.  They were popular in the 1940s.  The wind up is on the wood bottom and the tune plays when the lid is opened.  Still works fine but the song is unknown.
 
Very unique item and in great shape!  Measures 7" across and 4.5" tall.