Peridot Beads
Peridot is the name used for all the gem varieties of the mineral olivine, which also known as forsterite. Pure forsterite has no color. Iron atoms replacing some of thee magnesium atoms, give the stone its green color. The more iron, the darker the peridot. The most valuable peridot has a velvety gold-green color.
Although most gems form in the Earth’s crust, there are two that crystallize in the high temperatures of the liquid mantle: diamond and peridot. Studies of a peridot deposit in Arizona revealed that the green crystals were formed on rocks that floated in the mantle somewhere between 20 and 55 miles beneath the Earth’s surface. A volcanic eruption forced these stones up into the crust, near the surface, and weathering and erosion finally allowed them to be close enough to the surface to be found. Interestingly, peridot has also fallen from the sky. In 1749 a meteorite crashed into Siberia and was found to contain the beautiful olivine.