PAINTING AND DIGGING
On the other end of the spectrum are what is known as "painted girdle facets". Painting is, in a sense similar to digging except the facets are oriented in a different direction. For example in digging we've noted that the angles are steeper while in painting the angles fall shallow. Note the girdle thickness at the halves are now thicker than the girdle thickness at the bezels disrupting the consistency of the girdle.
Here's a profile via Helium of a diamond with painted upper girdles alongside classic and dug out for comparison.
Examining the girdle graphs we can see and note the differences as well. In the painted girdle we can note the obvious differences in unevenness except those differences in girdle thickness are now at the bezels and not the halves (bone).
The Sarin 3d model file also shows us these differences on a numerical scale.
Note the comparison. In essence when you compare the numbers its as if the dug out and painted girdles are reversed. In these examples the upper girdles are steeper on the dug out girdles and the upper girdle angles are more shallow on the painted girdle. Lower girdle angles on all examples are basically the same (being around the 42° zone).
Red Reflector images of diamonds with painted girdles appear like this one on the far right.
| ||Classic Girdle||Dug Out Girdle||Painted Girdle|
From the photography we can see the greater distinctions through our DiamXray technology as opposed to standard Ideal-Scope images, however AGS ASET shows more and other interesting detail. Take note of the concentration of green around the upper girdle region. As in the dug out girdle, this painted stone is drawing more light from the hemisphere as opposed to directly from above. While these may seem like minor issues to some, to others, anything that decreases brightness is indeed an issue. In GIA's observation testing the majority of observers noted the decrease in brightness, so much so that these as well do not make GIA's top grade. As of this publishing (2/24/06) stones with painted girdles will make AGS Ideal grade and points out one of the distinguishing factors between the 2 cut grading systems. Very interestingly ASET Technology explains the darker appearance in both the painted and dug out girdle types.
As an advocate of reflector technology and the science behind them, there is one technology I place far and above any of the ones we employ in our purchasing decisions. That one technology is perhaps the only one our clients go home with at the end of the day and that is their own set of eye balls. We have taken it upon ourselves to do our own observation testing in our store and have shown these above examples to the public simply to get consumer input from folks who could only best be described as typical "laymen". In each and every instance when we showed our clients the comparison of these 3 diamonds, it is safe to say that greater than 95% of all the people we interviewed could pick out the brightest diamond of the lot and each and every time it was the stone with the classic girdle. Very interestingly ASET Technology explains the darker appearance in both the painted and dug out girdle types.