This is a RARE old butterfly pin! It is a type of butterfly jewelry that is rarely seen. Production of pieces like this was very limited. 

This butterfly dates from the late 1940s or early 1950s and although it is not signed, it was made in Japan. The openwork design has an Art Nouveau influence and the butterfly is made of Japanned metal, or black enamel over silver pot metal. Yes, this is a pot metal piece ! 
The butterfly has 4 small clear rhinestone chatons on the wings and body. 

This is a medium large pin that measures 2 1/8" wide x 1 1/4" tall, or 5.4 cm x 3.5 cm. The entire piece is in pristine condition with no signs of wear or other imperfections. There is no loss of black enamel and the pin has the original fine working safety clasp. 
 
Comes gift wrapped and shipped in a new presentation jewelry box. 

* You can add a gold or silver brooch slider to convert this pin to a pendant by checking the box.