1950s ruby and diamond fancy cluster ring

1950s ruby and diamond fancy cluster ring in platinum. Centrally set with a cushion shape mixed cut ruby in a rubover setting, bordered to top and bottom with ten round brilliant cut diamonds in square collet settings and flanked by four rectangular step cut diamonds in channel settings, to a cushion shape cluster with polished borders, pierced gallery and met to either side with raised trumpeting shoulders which smooth to a solid shank.