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Helenite, also known as Mount St. Helens obsidian, emerald obsidianite, and ruby obsidianite, is a glass made from the fused volcanic rock dust from Mount St. Helens and marketed as a gemstone. Helenite was first created accidentally after the eruption of Mount St. Helens in 1980. Workers from the Weyerhaeuser Timber Company were attempting to salvage equipment damaged after the volcanic eruption. Using acetylene torches, they noticed that the intense heat was melting the nearby volcanic ash and rock and turning it a greenish color. The silica, aluminium, iron, and trace amounts of chromium and copper present in the rocks and ash in the area, combined with the heat of the torches, transformed the volcanic particles into a compound that would be later commercially replicated as helenite.