P71313B Mt St Helens Green Helenite May Birthstone Trillion Bezel Set Sterling Silver Pendant Stone Type: Helenite Stone Origin: Skamania County, Washington, USA Total Stone Weight: 3.85 Carats Stone Size: 13mm x 13mm Metal: Solid 925 Sterling Silver w/ Rhodium Finish Silver Weight: 2.61 Grams Suggested Retail Price: $90.00 *Earrings NOT included at the listing price. *The cutting of the stone might be different from what is shown on the photos, depends on the availability in stock. 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.