The necklace measures approximately 16 and 1/16 inches long, from end to end, and should fit at about 16 inches long, closed. The black rhinestones measure just over about 1/8 of an inch, or approximately 3.5 millimeters, wide. The large central clear rhinestone measures approximately 13/16 of an inch, or about 20.6375 millimeters, wide. The center drop is about 2 and 3/16 inches high. The fancy Sterling chain portion measures just over approximately 1/16 of an inch, or approximately 2 millimeters, wide. (Included you will find a US Quarter in the photographs, for the measurement-challenged and ruler-averse.) Stamped, "Sterling", on the back of one black rhinestone setting, stamped, "Sterling", again on the spring ring clasp, unsigned. Weight is approximately 10.38 grams, which includes the rhinestone weight, of course.
This old necklace is in very good vintage condition. It will have the expected surface scratches and normal wear. No visible cracks to the rhinestones, but there are some with tiny chips which are not noticeable when worn.. The spring ring clasp works as intended and holds securely. Hand polished, but it's likely that some tarnish remains.