Bandeau ring in yellow gold and tourmaline

18k yellow gold (750/1000) ring set with square colored stones and brilliant-cut diamonds: an amethyst of approximately 0.23 ct, a blue topaz weighing approximately 0.40 ct, a green tourmaline weighing approximately 0.29 ct, a citrine weighing approximately 0.28 ct, a garnet weighing approximately 0.33 ct, and two diamonds weighing approximately 0.01 ct each (each diamond weighs approximately 0.005 ct). Ring size: 55. Band width: 0.54 cm. Total weight: 3.92 g. Owl hallmark. Excellent condition.