R6418S Classic Mt St Helens Blue Helenite November Birthstone Emerald Cut Prong Set Sterling Silver Ring Gemstone: Helenite Stone Cut: Rectangle Stone Size: 7 carats Stone Dimensions: 10mm by 16mm Metal: 5.1 grams of 925 Sterling Silver with Rhodium Color: Blue Setting: Prongs Origin: Washington, USA *Because we use natural stones, the stones may vary slightly in shape, size, and color. * About Helenite: Helenite is a gemstone that resulted from volcanic ash and rocks and is also referred to as emerald obsidianite, Mount St. Helen obsidian. The volcano erupted on May 18, 1980, and ejected igneous rock from 10-20 miles underground. The fury of the volcanic eruption is a wondrous occurrence in nature. The beauty that has been created from itHeleniteis a fantastic thing to hold.