When we take a look at the big auction houses of the world, it becomes quickly apparent that blue and pink diamonds always make the headlines. In the November Auctions in Geneva in 2015 these two colours proved this in an impressive way. Yellow diamonds in the levels intense yellow and vivid yellow are also appropriate for investment purposes. Red, orange or green diamonds would also be. However these colours are much rarer than the former and it is difficult to get hold of even one beautiful stone let alone have a choice of stones to choose from at the same time.