This is a beautiful locket which , most likely, has held a miniature. It is 18 carat with glass on both sides, and the front contains a lovely mat with pink and blue enamel. What a lovely way to display a cherished photo or portrait miniature. This piece is in excellent condition, and circa 1840. It measures 1 and 3/4 inches North to South, including bale, and 1 and 1/4 inches East to West. The opening for the miniature is 7/8 of an inch North to South, and 5/8 of an inch East to West. The piece could hold a miniature 1 and 1/8 inches North to South, and 1 and 1/4 East to West. The mat would then cover some of it. If you are interested in this piece for portrait miniature, the best thing to do would be to send me a paper pattern of your piece, so I could put it in the frame and see if it fits. Most photos could be cut to fit.