Peridot has a Rhombic crystal system and is in the mineral class of Island Silicates. It is formed in deep rock out of ultra-alkaline magma. It is most often ripped away and brought to the surface by the rising magma during volcanic eruptions. Peridot can be almost colorless, green, olive green and as a yellow-green in its coloring. The yellow-green found in the Hawaiian Islands is many times referred to as “Chrysolite”. The deeper olive green types found in Europe are generally called “Olivine”.