18KW SEMI-MNT RNG W/TWISTED GALLERY UNDERNEATH 4-PRNG HEAD. 8.5MM RND CZ CNTR, 8.46MM TALL. 16 RBC DIA, IN SHANK, 8 EACH SIDE. 16=0.18CT. SHANK IS 1.62X4.25MM AT TOP, 2.77X1.7MM AT BASE. 3.4DWT SERIAL #756786