7/8" with the porcelain disc set into a brass frame with barpin on reverse. On the front lower right there is just a .25" hairline sliver where the porcelain was cut, as made, on a bit of an angle and thus there is just a hairline of space between the porcelain material and the brass rim edge. While this shows it diminishes the beauty of the piece very little. Back of the item is inscribed with maker's name "O'Hara Dial Co. Waltham, Mass." These porcelain pieces by O'Hara were done around 1896 for both the L.A.W. as well as 1896 McKinley and Bryan campaign items but the firm's main product was watch dials. Mint as made.