These gold tone screw back earrings are marked Coro in script with no copyright symbol. The high quality gold tone plate is indicative to the higher end Coro pieces manufactured during the 1940 - 1950s period and patented by Adolph Katz; I was not able to identify the patent number. Earrings feature kite shaped clear rhinestones in a teardrop open cut design. They measure 2 inches in length and 11/16 inches in width and are in very good vintage condition. Perfect for a special occasion!