This is a stunning antique Mikimoto Japanese akoya saltwater cultured pearl cluster brooch.

The pearls are 5.00-5.25mm round. They have fantastic luster with rosy pink overtones. 

It is made of solid sterling silver and has lovely hand engraved and milgrained details. It is stamped "M" in a clamshell for Mikimoto and "SILVER" for sterling silver. It measures 2 1/4 inches long. From Japan 1910's-1940's. It has an old style trombone clasp

All pearls are truly vintage and have only been lightly cleaned. Some patina on the back.