An Important Platinum, 18 Karat Yellow Gold, Burmese Ruby and Diamond Ring, Oscar Heyman Brothers, containing one cushion cut ruby weighing approximately 6.05 carats and two half moon brilliant cut diamonds weighing approximately 1.50 carats total.Stamp: 301025 (maker's mark for Oscar Heyman Brothers) IRID. PLAT. 18K.Accompanied by a Gem Research Swisslab gemstone report number GRS2005-050821, dated May 18, 2005, stating: Natural Ruby, Weight: 6.05 Carats, Origin: Burma (Myanmar), Comments: Heat H(a), no surface cavity fillings.Accompanied by an Oscar Heyman Brothers certificate of authenticity, dated May 2006, stating the serial number 301025, the metals of 18 karat and platinum, and stones as 1 cushion Burma ruby weighing 6.05 carats and 2 half moon diamonds weighing 1.50 carats. 4.40 dwts.