George III diamond and enamel navette form ring

George III diamond and enamel ring, the navette-shape blue guilloché enamel plaque scattered with seven old cut diamonds within white enamel border and surrounded by a further border of old cut diamonds in silver collet setting on gold reeded shank. Estimated total diamond weight approximately 1.1ct. Ring size N½.Condition Report The head measures approximately 21.74 x 14.72mm. Excellent condition commensurate with age. Enamel is in excellent condition commensurate with age. The diamonds all appear to be original to the ring, estimated I/J colour and SI2clarity. Weighs approximately 6.47 grams.