Vintage Antique Platinum Natural Diamond Art Deco Solitaire Engagement Ring

True vintage Art Deco diamond platinum solitaire ring. I'm guessing 1920's to 1930's. This unique and beautiful ring features a single brilliant cut diamond of approx. 0.20 carats, surrounded by geometric Art Deco engraving that extends to the half-round platinum shank (stamped Plat). This ring is perfect for a small hand and for extended wear. It is light and comfortable. The stone sits low enough to wear gloves over the ring, and the prongs do not catch on fabric. It is in excellent vintage condition. There is mild surface wear consistent with age, but no actual damage. Ring size: US size 5 1/4, UK/AUS size K Band width: 1 mm at base of shank, 2 mm closer to shoulders Band thickness: 1 mm Height above finger: 5 mm