Set gemstones, gemstone settings, and methods of setting gemstones including a cut gemstone having a girdle a plurality of horizontal grooves each having an upper edge and a lower edge, wherein the upper edges of the plurality of horizontal grooves are located within the girdle, abut a lower edge of the girdle, or are within 1 millimeter beneath the lower edge of the girdle, and a cylindrical barrel having a central aperture, an open top, a rim at the top forming an upper edge of the barrel, and a plurality of flanges projecting into the central aperture of the barrel located directly beneath the rim, wherein the flanges project into the grooves to maintain the gemstone within the barrel.