How Many Facets?

[dreamycastle]

Dear posters

I have a query, someone enlighten me on how do i see how many facets a GIA certified diamond has? Where can I get this information. I am looking at a round ideal cut from WF. Does it matters whether it is 57 or 58?


Thanks!

 

[valeria101]

''Guess it is a round brilliant... and they all have the same facet pattern. Some count the culet as the 58th facet. Matter of theory, I''d guess... for these diamonds with ''pointed'' culet. There''s nothing there to count!

I am not sure if this answers the Q.



In fact, I don''t think there is a way to see how many facets a diamond has, by reading the GIA report: the name of the cut implies a certain facet arrangement, and at least for some shapes the drawing on the clarity plot at least matches the facet pattern (i.e. also the number of facets for what that matters). Fancy shape diamonds may not be exactly represented by those drawings...

This is about all that comes to mind.

 

[JohnQuixote]

Date: 2/28/2006 10:31:16 AM
Author:dreamycastle

Does it matters whether it is 57 or 58?

The short answer: A round brilliant with no culet is a 57 facet diamond, while one with any culet is a 58 facet diamond.

A longer answer: The culet is a tiny flat facet that may be polished onto the bottom of the pavilion of a diamond, parallel to the table facet at the top of the crown.

Most modern round diamonds have either no culet (also described as pointed or closed), or a very small, or small culet. Large or extremely large culets were common in diamonds cut in the early part of this century, such as the Old European or Old Mine Cut. However, such large culets are rarely seen today.

For many years all diamonds had the culet facet added to protect the tip of the pavilion from being chipped or damaged. Diamonds used to be set very low in jewelry and often the pavilion actually contacted the skin of the wearer’s finger, thus greater risk of damage to the exposed tip. A culet of medium size or larger may adversely influence light return, since such a facet is effectively a hole in the center of the diamond. Modern jewelry styles raise the pavilion of the diamond. The setting itself usually provides sufficient protection for the pavilion from impact and wear, so there is no need to add a culet. Any culet medium or larger is now rare.

 

[smappraisal]

Hi,
All the above is accurate and I''d like to add one technical point. On a GIA cert, once in a great while, you may see a plotting symbol of EF. This would be an instance of an Extra Facet. This external characteristic is not going to be found on well cut stones. They usually occur where Lower Girdle facets, Pavilion Mains and underside of Girdles meet. It is an attempt by the cutter to correct a cutting miscalculation, whereby the points of a Pavilion Main and the point of the Bezel facet above it (on the upper side of the Girdle) do not align correctly. In other words, professionally it is considered to be a misalignment and therefore an issue of Symmetry.
As it relates to your question, in a case like this, the stone could have 59 facets, assuming there was a faceted culet. Once again, it is not something that your going to see with GIA EX/EX or VG/VG stones, but I thought it was worth mentioning.

Stephen Marino, GG
Professional Appraiser
Boston & vicinity

 

[dreamycastle]

Thanks everyone on these input. Very iteresting read indeed!