The famous Diamond is the birthstone for people born in April. Diamonds are one of the rarest gemstones in the world and certainly one of the most prized. They earn that recognition partially for how hard they are, in fact they are 58 times harder than any other mineral on Earth. That is why you will often see diamond coated blades and bits as they are able to cut or grind through anything. Discover Diamond Jewellery by the world's most exciting designers.