One Possible Scenario
Lets look at a possible scenario to illustrate the potential financial loss for the unwary. A man brings you an impressive looking diamond, mounted in a beautiful bezel-set ladies ring and asks you to make an offer on it. You look at it in awe trying to measure the diameter, but you’re having difficulty with the bezel covering 360 degrees of the edge of the round brilliant cut diamond. The pavilion is fully enclosed so a depth measurement is out of the question. You check the color with a comparison stone and judge the appearance to be an “H”. Under 10x magnification inclusions are small and insignificant but to be safe you assign an SI1 clarity grade to it. The stone spreads 6.7 mm, adding a little extra for the covered edges of the diameter. Again, you take a conservative approach, offering an amount that would leave a fair return on your investment. The man accepts your offer and leaves.
After the loan or hold period has expired, (if applicable to you) you anxiously have the diamond carefully removed by a goldsmith who shaves the bezel away to expose the edges of the diamond. After the diamond has been removed, you clean it so it can be graded accurately. Now comes the disappointment. It only weighs 0.87 when you expected a 1.10+. The color is a “K” at best and the clarity is still an SI1+ but there are many small chips and nicks around the perimeter of the stone. A re-cut is necessary for resale purposes.