Jewelry manufacturers started to use platinum metal for designs at the turn of the 20th Century. Once it became a common practice in the industry, platinum became the precious metal for diamond rings.   The 1920’s period was known for the Art Deco style that also influenced jewelry designing. The rings of the era are characterized by sharp lines as well as geometric designs, which are made up of several small diamonds when it comes to jewelry. In the 1930s, multiple gemstone rings came to be a popular trend. During the period of the Great Depression, large flashy jewelry pieces took a backseat for most people in the US, except for the extremely rich. The 1930s ring styles were more simple though, with a tendency to feature a bigger (often round cut) gemstone at the ring’s center instead of the numerous diamonds as seen in the 1920s. Still, platinum continued to be the top precious metal of choice for the 1930’s engagement rings. In fact, you could still find a vintage 1930 diamond ring with the lavishness of the Art Deco style in platinum.