18k two-tone diamond and ruby necklace rectangular pendant centered with a tube-set oval-cut ruby weighing approximately 1.60 ct, surrounded by 191 pavé-set round brilliant-cut diamonds and openwork with milgrain detailing, finished with tube-set princess-cut rubies weighing approximately 1.00 ct, connected above to a yellow gold chain by a diamond cluster with ruby accents, length approximately 28cm, total weight 17.56 grams 1