A Stunning Antique Ostby & Barton Tiffany Set Rose de France Amethyst Wedding Ring in Vintage Victorian - Early Art Deco White Gold Setting, circa 1900-1920's. The setting was made by Ostby and Barton, one of the leading jewelers of fine jewelry at the Turn of the Century. The setting is marked OB, the mark for Ostby Barton. One of the founders of Ostby Barton parished on the Titanic, making their pieces historically interesting. This exquisite ring holds a lovely Rose de France amethyst its center measuring about 7mm in diameter. The cut of quite unusual and original to the setting. The setting is of gorgeous quality and is composed of 14K white gold with crisp detail, representing some of the best workmanship of the Era. Overall the ring measures about 3/8 inch long by about 3/4 inch wide from side to side. Ring Size: about 8 (could be resized by your jeweler or ask me about using mine before shipping). This ring dates to the late Victorian to early Art Deco period and is in exceptionally nice vintage condition. A rare find.