Gemstone few as one in a million atoms. These so-called impurities are sufficient to absorb certain colors and leave the other colors unaffected. For example, beryl, which is colorless in its pure mineral form, becomes emerald with chromium impurities. If manganese is added instead of chromium, beryl becomes pink morganite. With iron, it becomes aquamarine. Some gemstone treatments make use of the fact that these impurities can be "manipulated", thus changing the color of the gem. Gemstones are often treated to enhance the color or clarity of the stone. Depending on the type and extent of treatment, they can affect the
Helenite of its emerald-like color, good refractive index, and durability. It is seen as an inexpensive alternative to naturally occurring green gemstones like emerald and peridot. Helenite can also come in various red, green and blue varieties. Helenite Helenite, also known as Mount St. Helens obsidian, emerald obsidianite, and ruby obsidianite, is an artificial 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.