Rose Yellow Guilloche Enamel Mid Century Silver Scandinavian Earrings

The guilloche enamelling is synonymous with Norway with a number of workshops producing wonderful enamel work. I have seen these earrings attributed to Opro, a company which began in Norway in the early 1970's, however with no company mark other than the sterling silver mark I can not be sure of the exact company. They are screw back mechanism and in perfect condition There were other mid century companies in America who seem to have produced similar designs. A beautiful vibrant yellow guilloche enamel with hand painted rose on sterling silver. Measurement is 1.5cm square. Gift boxed by Vintageonline.