1960s Art Deco style bezel set diamond solitaire in two tone gold

1960s Art Deco style bezel set diamond solitaire in two tone 18kt gold. Set with an estimated 0.40ct round transitional cut diamond in a floating bezel setting, to a sleek solitaire design with smooth setting framed by a bombe border ribbed to the front and engraved and chaised to the inner with scrolling, leaf and foliate motifs in 18kt white gold, continued to the shoulders before smoothing to an 18kt yellow gold shank. Tested 18kt gold.