Metal Bands Jewelry designers commonly used platinum in both Edwardian and Art Deco rings, but if it features white gold, it is likely to be from the late 1920s and the early 1930s.     Repetition and Symmetry While Edwardian styles are not very likely to be symmetrical, Art Deco rings have calculated and extremely noticeable symmetry. This symmetry in repeating patterns carries through Art Deco diamond rings, comprising accent gemstones and into the metal band. Popular Center Stones Centerpiece diamonds are a go-to choice in both periods, but in a 1920s diamond ring, you are more likely to see colored gemstones that highlight a particular pattern. In contrast, an Edwardian ring is more likely to be paved with several small diamonds. Angles or Curves If the rings have flowing and graceful curves and lines, which resemble bows or ribbons, they are likely to be one from the Edwardian period. On the contrary, an Art Deco ring will have straight lines and sharper angles, displaying modern architecture in particular.