What do the mean by "diamond accent" is it not real diamonds?

A diamond accent must be a real diamond unless otherwise stated, but it is a very small one, sometimes incredibly small and is there to help throw light into the main stone. One carat of diamonds is equivalent to one hundred points of diamond and an accent stone can be as small as a third of one point , so it should be regarded simply as part of the design rather than as adding much to the value of the piece.
There are exceptions of course...at the high end of jewellery manufacture you will find rings with accent stones as large as ten points and possible more, in which case they do add considerably to the intrinsic value of the piece.

Пояснение см.
http://answers.yahoo.com/question/index?qid=20071208223951AARIulr

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