This is a nice pair of 14k earrings.  

The opals are doublets and the post earrings measure about 1/8” x 5/16” x 7/16”.  

They are marked 14K on a plaque on the back of the earrings.  

The definition of opal doublets:  “Opal doublets are an assembled form of opal. A doublet is a combination of a precious natural crystal or light opal and a veneer of black potch. These are bonded together to create a doublet which emulates the brightness of color found in black and dark opals.”