Colour in diamond is generally caused by the accidental inclusion of trace elements such as boron turning diamonds blue and nitrogen turning diamonds yellow. In this case it is the presence of severe fluorescence causing opalescence which gives this stone a strong milky white colour. A dramatic change occurs when viewed under ultraviolet light. Some of the smaller diamonds on the mount of this ring show the same phenomenon. The designer has carefully selected these highly opalescent diamonds in order to create a ring that will have a dramatic appearance depending on the lighting conditions.