A ruby, black enamel and diamond dress ring

The plaque ring set with a collet-set oval ruby, weighing 4.89 carats, between brilliant-cut diamonds within a border of similarly-cut diamonds, within a millegrain setting throughout, to pavé-set diamond shoulders, diamonds approx. 2.0 carats total, ring size P

Accompanied by a certificate from GRS stating that the ruby is of Burmese origin, with no indication of thermal treatment. Report number GRS2020-071619, dated 20th July 2020.