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Hi, I'm Steve Moriarty from Moriarty's Gem Art. We represent ourselves online as moregems.com. Recently, on one of the faceting forums, a new cutter asked the question as to whether we should polish the girdle or not. I personally don't currently polish girdles so I told him no, but most everybody else said absolutely polish girdles. I'm not sure I believe this because the girdle is a reflecting surface that what light comes through the crown of the stone I don't believe will ever reflect off of the girdle facets, and end up coming out the top of the stone again as brilliance. But, I don't know that for a fact. I quit polishing girdles quite some time ago because a lot of the stones I cut, which would include appetites, emeralds, sphalerites, are a little more delicate. I've had some issues where when you go to polish a girdle, which typically you do last, I've had them chip on me, which means often re-cutting the whole stone.

 

So, I quit polishing girdles because I did not believe that it would have an effect on the brilliance, but I'm going to find out for sure. So, what I've done so far is I took one stone, a citrine, that didn't have a polished girdle, and I re-polished it, and tried to take photos of it, and before and after, but it was very difficult to see if there was a difference in the brilliance. So now I've decided to cut two identical stones, and then compare the brilliance, and see if we can actually see the difference. So what I've chosen in some material zircon, because it's a nice brilliant stone. I'm going to cut my form of a modified round brilliant, and try and cut to the same size, the exact same faceting, and see if we can actually see a difference in the brilliance. I may later do an oval also in citrine, just to try and really find out whether it does have an effect or not. So polished girdles or not, we're going to try and find out.

 

This is the first stone I'm doing, which is a zircon. It's currently reddish brown, but I'm going to heat it to colorless, and try and get them both to a near colorless state so it will be easier to see just what the brilliance is. So we finished two pairs of identical stones, and it's turned out to be something very difficult to prove whether faceted girdles, or I should say polished girdles, or unpolished girdles are more brilliant. In the case of the two zircons we cut, I've heated them, they're white now, but unfortunately the stone with the polished girdle has a little bit of haziness to it caused by clouds in the stone. So, it really wouldn't give an accurate representation of the brilliance of the stone. The citrines are much better. They're clean, very slight difference in color, but both of them have identical cuts. We'll talk more about the citrines than the zircons because they just don't apply.

 

So in the video the stone on the right has the polished girdle. The stone on the left is the unpolished girdle. The videos are difficult to determine which one's more brilliant because there's factors involved like where the lights were positioned, and so it does make it difficult. But, the biggest determination was I gave it to five different jewelers, had them walk around with them, look at different lights, and try and determine which was more brilliant. Not a one could distinctly, or definitely say that one was more brilliant than the other. I agreed with us, and nobody knew which one was the polished one, and which one was the unpolished girdle. So in my opinion, looking at the stones you really can't see the difference between the brilliance of a polished girdle and an unpolished girdle. This might be verified more by cutting synthetics that are absolutely the same, but I'm pretty much done with this trying to determine which is more brilliant.

 

To me, there is so little difference in the brilliance that the extra time may not be worth the effort because if I cut 500 stones in a year, by not polishing the girdles, I could cut an extra 33 stones, which even at $200 is another $6,000, $7,000. So for me as a commercial cutter, it may not make sense to polish girdles. Although, there are times that I do polish girdles when they're a little thick, or they're very long facets they tend to show up more. Some colors show it more. So I do polish some girdles, but I'll continue to generally not polish girdles just for the time involved. For those of you who are cutting for competition, or really do not cut a lot of stones and you want the stone to be perfect, go ahead, polish the girdle, but don't expect that it's going to be a much brighter stone because you did this.

 

So I want to thank you for watching. If there's any of you cutters out there that would like to go further into this and cut your own stones, I'd be very interesting. I'd recommend cutting some type of synthetic. Make sure you're on the same axis, and that it's very clean, and send me your results. So if you want more information, you can check us out online at moregems.com, or Moriarty's Gem Art.

 

Thank you,
Steve Moriarty