EDCO is a well known manufacturer of rings made with various materials, including gold tone, silver tone, 925 sterling, 14 & 18 KTGE Gold Electroplated. Rhinestones, Cubic Zirconia, and various gemstones, Sapphire, Amethyst, Ruby, Topaz. This is a vintage, signed EDCO it’s stamp on the inside of the band that appears to be 18KTGE. The gorgeous very large oval London Blue Topaz is surrounded by 24 prong set white diamond CZs, crystals (or glass, however unlikely.) i cannot express the frustration that I cant catch the color on an app. The Topaz in some light appears Blue Sapphire! The closest color I’m able to adjust to is the first one, but trust me, it’s beautiful in any light! Excellent condition but for some microscopic scratches on the underside of the band seen with a jewelers magnifying loupe, otherwise in perfect condition. Size 7 as shown in the photos. Stone size measures just under 3/4”L X just under 1/2”W at longest/widest points. The setting is almost 1” X almost 3/4” to the edge of the diamonds. I cannot guarantee any of the information on this ring except to say it is stunning and made by EDCO who is known for the type, style, metals and stones I am assuming this ring follows, and retails and is priced as such.