Treated yellow diamonds undergo cyclotron bombardment to produce a deeper more attractive colour than their original colour. Probably the most famous treated yellow diamond is the "Deepdene", a 104.53 carat cushion-shaped stone, which was first offered at Christie's Geneva in 1970 and sold in November 1997 for the outstanding price of $715,000. As long as there is full disclosure, a buyer should not be detered from buying a treated diamond as it is still created by nature but enhanced by man. The treated yellow colour seen in the following two lots, 375 and 376, are close to the natural vivid yellow colour of diamonds and still make desirable jewels.