Diamond and pearl drop earrings

Hard to see the stamps there are two on each earring at the base of the post on the lever side.   I can't clearly make out but one says 915 and the other I am told is 2/3, it's a fraction.  I will add more photos from a better camera in a few min.  Similar items go from $1200 all the way to $3200.  I need help figuring out who made it and from what era