Tommaso Design 8x6mm Emerald Octagon Cut Simulated Alexandrite Engagement Solitaire Ring 10kt Gold Metal: 10 kt White Gold. Dimensions: Width: 9.00 mm Length: 7.00 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. SIMULATED ALEXANDRITE: The Simulated Birthstone for June. Named after Czar Alexander II of Russia, this very rare gem has the ability to change color. A symbol for change, Alexandrite is said to inspire imagination, creativity and confidence.