Tommaso Design 10k White Gold Octagon Emerald Cut 8x6mm Solitaire Promise Engagement Ring Metal: 10 kt White Gold. Dimensions: Width: 6.00 mm Length: 8.00 mm This Classic creation is made by the renowned Tommaso Design Studio. Tommaso Design Studio, is a reputable American Family Business based in New York since 1986, uses the highest quality materials, and will proudly stand behind all of its products. White Topaz: The Substitute Birthstone for April. Named from the Greek `topazos` meaning `to seek`. Topaz occurs in a wide range of colors, and is said to enhance spiritual potential, intelligence, creativity wisdom and wealth. Additional Stones: