This is a lovely vintage art deco marcasite and Japanese akoya saltwater cultured pearl bar brooch.  

The pearls measures 7.00mm and have great luster with rosy pink overtones. They are set into four prongs.

It is made of solid sterling silver and has lines of bright and lively marcasite stones. Very detailed with marcasites throughout. (None are missing). It measures 1 7/8 inches long. Stamped "STERLING". 

All pearls are truly vintage and have only been lightly cleaned. Has a fairly heavy patina on back.