These are a vintage pair of Mikimoto Japanese akoya saltwater cultured pearl mid century circle screwback earrings. 

The pearls are highly lustrous with rosy overtones and measure 6.00mm. They are set among a circle design with a single milgrained and engraved leaf. 

They are made of solid sterling. Stamped "M" in a clamshell for Mikimoto and "SILVER"  for sterling silver. Measure 11/16 inch high. From Japan 1940's-1980's.

All pearls are truly vintage and have only been lightly cleaned.