Centering on an oval sapphire within a round diamond surround

Metal: 18k gold
Diamonds: 12 round diamonds
Sapphire: 1 oval shaped measuring approximately 6.48 x 5.18 x 3.35 mm and stated to weigh
Certificate: With report 1192028153 dated January 29, 2018 from the Gemological Institute of America stating that the origin of the sapphire is Cambodia with no indications of heating. Accompanied by copies of customs invoice and paperwork from Cartier, London dated September 21st, 1976
Size/Dimensions: US ring size 6.25, 1.3 cm at widest point
Signature: Cartier
Marks: 18CT, numbered (partially obscured)
Gross Weight: 3.4 grams
Accompanied by Cartier box