Explore diamond engagement ring White Rock at Pure Diamond. We understand the need for a white metal because whichever metal you choose beneath your near-colorless diamond will refract light. A white metal, such as platinum, will reflect white light, allowing your diamond engagement ring White Rock to shine to its full potential. So, while there is a price difference between platinum and gold, platinum is a rarer metal than gold, it is hypoallergenic, and it will retain its naturally white hue forever, all of which are significant advantages during the lifespan of the ring.