Dark areas in princess diamonds

[DK]

About a year ago we had a local jeweler/goldsmith make a new wedding band for my wife that contains 9 channel-set, princess-cut F/VS2 diamonds, each weighing about .16 ct. We noticed that, in certain indirect or subdued light, noticeable dark areas or shadows appeared in the diamonds. When we showed this to the jeweler, he said that it was a normal "bow-tie" effect that is also seen in marquise or pear diamonds. It does not seem to be caused by inclusions because the dark areas disappear in stronger light. Now that I have learned more about the importance of precision cutting, I wonder if the dark areas are the result of poorly-cut princess diamonds. I would appreciate any input on this. Many thanks.

DK

 

[Richard Sherwood]

Dark areas are usually areas where light is leaking through the stone instead of being returned to the eye.

Most stones will have them somewhere, especially fancy cuts. The less, the better.

The round brilliant is the best cut for reducing light leakage, because it's round symmetry produces a very good "house of mirrors" effect, with little light escaping through the bottom.

Marquise and pearshapes will have a darker "bowtie" area in the center of the stone, while princess cuts tend to get darker in the North-South-East-West quadrants under the table.

 

[DK]

Richard,
Does this mean that if the dark areas are more pronounced in some of the diamonds that their cut is of a poorer quality?

 

[Richard Sherwood]

Probably.

 

[DK]

Would you recommend that I go back to the jeweler/goldsmith who made the ring and have the diamonds with the pooer cuts replaced?

 

[Richard Sherwood]

Well, there's a couple problems with that.

One, with the princess cuts being channel set, you would have to destroy the mounting in order to get them out of there.

Two, if you're thinking the jeweler should replace them at no charge, I would have to point out that the sale was made a year ago, and you approved the transaction and accepted the goods. The jeweler really has no obligation to replace the stones at no charge.

If it's really bugging you, I would say your best course of action would be to ask the jeweler if you could "trade up" to a ring with finer cut stones. You should, of course, be willing to pay the difference.

 

[DK]

Richard,
Thanks for your help. I appreciate it.