This is a lovely quality petite necklace shortener or accessory made of four Japanese saltwater akoya cultured pearls. 

The the pearls are highly lustrous with rosy overtones. They measure 4.50mm. Some light blemishes.

Measures 7/8 inch. It is petite. Not stamped but tested and guaranteed solid 14K yellow gold. From mid-century. It is not a sharp pin for clothing but clips over a strand of pearls as an access or to shorten it. 

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