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

The the pearls are lustrous with rosy overtones. They measure 3.50mm. Some light blemishes.

Measures 3/4 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.