Opal is unique versus other gemstones and is able to display a rainbow of colors through the diffraction of light. This iridescent pattern is caused by tiny spheres of silica within the opal. Depending on the size and how the spheres are placed causes different colors to show on the stone depending on how light is shining on it. Revolution Jewelry offer a variety of crushed opal that can be used as exterior inlays on our rings.