A ruby and diamond cluster ring

A ruby and diamond cluster ring, mid 20th century, set with an oval ruby weighing approximately 1.25 carats, within a border of brilliant-cut diamonds, mounted in platinum and white gold, size N1/2

Accompanied by Gem & Pearl Laboratory report no. 22030, stating that the ruby measuring 7.4 x 7.1 x 3.4mm is of Burmese (Myanmar) origin, with no indications of heat treatment