Recutting Sapphire

[adams828]

Hi all - I am in the process of looking for a sapphire e-ring, and have been in contact with a few of the vendors from the site, however so far the right stone hasn''t come up. I know it can be a lengthy process, however, I see some sapphires on simply sapphires that while the size/color/price seems right, the cut doesn''t seem necessarily the best.

While it seems that overall the preference of most cutters is to not re-cut gems, it seems like it may be a great solution for me. Does anyone have any experience doing this or can recommend a cutter who is more open to this approach?

Thanks!

 

[Indylady]

If I were you I would probably shoot an email to Dan Stair; he''s really very kind and helpful, so I think its certainly worth a shot. He also might be able to see if he has rough in the color that you''re looking for and then cut you a custom stone. Hope that helps!

 

[D&T]

try Jeff White at whitesgem.com or Barry Bridgestock at acstones.com or Michael at gemshoppe.com Gary at finetwatergems.com as well, all great cutters to work with and see if they also have roughs.

 

[kas baby]

I agree that it can take a loooong time for the right one to turn up. but definately worth the wait, I''ve been engaged for over a year now, and the right sapphire just turned up. I am working with Jeff White, he''s really great to work with, super nice guy. I think it just happened to be perfect timing. I had also contacted Gary from Finewater, he was also very nice and very willing to keep an eye out. Those are the two from my experience, but definately consider the others mentioned above.

Hang in there, and contact a couple people. It''s always good to have more eyes out on the lookout

 

[chrono]

Date: 7/25/2009 6:06:01 PM
Author:adams828
Hi all - I am in the process of looking for a sapphire e-ring, and have been in contact with a few of the vendors from the site, however so far the right stone hasn't come up. I know it can be a lengthy process, however, I see some sapphires on simply sapphires that while the size/color/price seems right, the cut doesn't seem necessarily the best.

While it seems that overall the preference of most cutters is to not re-cut gems, it seems like it may be a great solution for me. Does anyone have any experience doing this or can recommend a cutter who is more open to this approach?

Thanks!

There is a very good reason for this; if the stone could have been cut better, it would. Also, some of the native cut stones are cut that way to preserve weight and make the best of the colour. If recut, it may end up with colour zoning, an inclusion might be in the way, or some other problem might crop up.

I don't know how long you have been looking, but for an e-ring, I'd contact several vendors and let them do the search. You already have several good recommendations. These cutters will most likey source their own stones or rough because they are able to view it firsthand to be sure it is a good candidate for a recut.

 

[PrecisionGem]

Actually the reasons that most cutters won''t do recuts isn''t that it won''t improve the stone, but there are too many issues with doing this kind of thing. The finished size may be less than the customer thought, the stone could come off the dop, requiring even more loss in weight, and for me, it just isn''t fun doing recuts.
Normally recutting a native cut stone will improve color and can help hide color zoning. A windowed stone will show a color zone much more than one that has even brilliance all over. Usually the color intensity is better in a well cut stone. Native cut sapphires are ALWAYS cut for maximum face up size and weight. On smaller stones they are also cut very very quickly, and there fore the poor meets, poor polish etc. Rarely are these stones polished with anything close to what a US cutter would consider to even be a polish.

 

[Michael_E]

I''ll add a bit to what Gene said. Re-cuts for clients who have something in particular in mind can be a real tough nut. On the other hand, using pre-cut gems as rough can be a lot of fun with a whole lot less risk, since you can see exactly what you''re getting, inclusions and all. If a client has no preconceived notions about what their re-cut stone SHOULD look like, then they usually work out just fine,(assuming that the stone is a suitable shape from which to do a re-cut). If you''re looking to have a stone re-cut and approach it with a VERY open mind, you shouldn''t have any problem finding a cutter to do it for you. On the other hand, if you are quite specific about what you expect and that''s on the border of impossible, then you might have a much more difficult time finding someone who wants to deal with that.

Stone fall off the dop ?.....this is me when that happens--->

 

[chrono]

Gene,
I have to disagree with several of your opinions. I do not claim to be an expert but this is based on my discussion with other custom cutters and my personal experience with native cut stones that I commissioned. I have seen many recuts of native cut stones where the colour actually got worse and showed colour zoning which were not apparent in the original native cutting. After the recut, the intensity of colour and vividness was decreased and showed a stronger gray secondary. I do not feel comfortable showing examples here because it will put the cutters and stone owners in a difficult position as they are PSers as well. A few of my projects happened as such and now I no longer request recuts. To me, this is a risk consideration in recutting native cut stones. For me, colour trumps all. Of course, there are decent native cut stones out there as well and these are the ones I go for if it has the right colour.

 

[Michael_E]

Date: 7/29/2009 8:37:33 AM
Author: Chrono
I have seen many recuts of native cut stones where the colour actually got worse and showed colour zoning which were not apparent in the original native cutting. After the recut, the intensity of colour and vividness was decreased and showed a stronger gray secondary.

There is very little difference between a well cut "native cut" gem and a well cut "precision cut" gem. It''s the poorly cut gems which can give the rest a bad reputation. Typically a well cut "native cut" stone will be quite even, deep and have crown angles which are sufficient to have most of the light entering the stone bounce across the pavilion on a very short cross axis path before coming back out of the stone to your eye. That short bounce across the stone limits the contribution of color,(often grayish or greenish, in dichroic stones like sapphire), from the cross axis making the stone appear to be quite even and saturated in the preferred color when viewed face up. A "precision cutter" with not enough experience can make the mistake of thinking that re-cutting to a brilliant cut style will improve the stone, when it reality it will mess it up.

When I first started cutting sapphire I thought that having a short light path was the key to brightness in dark stones and actually cut a large 9mm round stone in a brilliant cut which ended up having acceptable brightness, but also had a very strange bullseye effect where the gray/green cross axis color formed a ring around the central blue. The moral of this story is that re-cutting is very complex, particularly in dichroic stones and one has to be careful about what they''re removing, where it''s located and why they''re doing it. Maybe 25% of native cut stones should be left alone as they can''t be improved, while the other 75% should be considered carefully when deciding on how they should be re-cut. This is the biggest problem with customers choosing a stone for re-cutting, as they often don''t realize what they should be looking for in a potential stone for re-cutting.

Here are a few of the things to look for in a potential re-cut:

1. Even color or poorly colored areas which will be removed. Pink tourmalines with ugly green fringes are a good example of this.
2. Color zoning is O.K. as long as it''s in an area where there are lots of angle changes to mix the color up, i.e, around the culet.
3. Deep shapes in darker stones, (not too dark though), that follow the above guidelines, as these can often be improved dramatically with a re-cut.
4. Lack of inclusions or inclusions which can be mostly removed or hidden from obvious view.
5. Poorly shaped stones. Sometimes you can get a real deal on things like marquise cuts which have very dark points and decently color mid-sections. If these are deep enough they can be turned into very nice and more evenly colored long ovals by rounding their tips, which brightens the entire stone significantly.
6. Broken, chipped or fractured stones of adequate depth. These can often be had at steep discounts and make a good starting point for unusual shapes like half moons or elongated ovals or cushions.

Re-cutting costs are usually pretty reasonable as long as your expectations are and if the up front costs of the stone to be re-cut is low, this can be a good way to get a nice stone for low $$.

 

[chrono]

An excellent and informative post. Thank you, Michael, for taking the time to explain it.

 

[PrecisionGem]

My only answer could be that the recuts were not good. A well cut stone will alway out perform a poorly cut stone. Most native cut stones are not carefully planned out, they are quickly cut in less than 1/2 hour, usually in an assembly line system. One person preforms, one dops, one shapes only pavilions, then on cuts and polishes in one step with a very coarse polish.
A good "precision" cutter may spend a few hours over the course of several days planning out a cut, designing it, testing the design with optimization software. Sapphires typically or the worst cut stones I see, usually the crowns are way too low to give any dispersion, the pavilions are either too deep to retain weight, or too shallow since the stones was flat, and they wanted to get a large face up size. A stone lacking in brilliance due to a window will show zoning much more than a lively brilliant stone.

I would be very interested in see pictures of some of these stones you talk about in before and after. Could it be you are looking at before shots that maybe the color was enhanced? Many of the websites selling stones, especially ebay dealers jack up the color.

 

[chrono]

Gene,

The precision cutters I am referring to in my earlier post are US Pricescope cutters (but you are not one of them). Since they are highly respected and used often, I’d rather not mention names. The recuts I have seen and experienced personally are spinels and sapphires. The pictures are not enhanced because they are posted by the gemstone owners themselves. The original stones are also not purchased from eBay but from reputable PS vendors. As mentioned earlier, I’d rather not post the examples due to a difficult situation I will be putting the gemstone owners and cutters in.

In my case, the cutter purchased the stones to be recut so he had the opportunity to handle and see the stones for himself to make sure they are a good candidate for recutting.

 

[T L]

Date: 7/29/2009 7:38:07 PM
Author: PrecisionGem
My only answer could be that the recuts were not good. A well cut stone will alway out perform a poorly cut stone. Most native cut stones are not carefully planned out, they are quickly cut in less than 1/2 hour, usually in an assembly line system. One person preforms, one dops, one shapes only pavilions, then on cuts and polishes in one step with a very coarse polish.
A good ''precision'' cutter may spend a few hours over the course of several days planning out a cut, designing it, testing the design with optimization software. Sapphires typically or the worst cut stones I see, usually the crowns are way too low to give any dispersion, the pavilions are either too deep to retain weight, or too shallow since the stones was flat, and they wanted to get a large face up size. A stone lacking in brilliance due to a window will show zoning much more than a lively brilliant stone.

I would be very interested in see pictures of some of these stones you talk about in before and after. Could it be you are looking at before shots that maybe the color was enhanced? Many of the websites selling stones, especially ebay dealers jack up the color.

Maybe in light return, but not always with saturation of color. Sometimes a recut can affect color adversely. That''s been my experience when sometimes seeing recut native cuts. If we were talking colorless stones here, then a good precision cut will probably always be better than a poor native cut. JMO.

 

[chrono]

TL,
My guess is that when a lot of material loss is concerned, it will affect the tone and saturation to some degree because the path of the light travelling through the stone is shorter. However, in some cases where only the pavilion was recut, I did not expect to see that great a decrease in saturation. I am not well versed in the intricacies of recutting so I’m hoping to get clarification from the cutters here on PS.

 

[T L]

I have a recut cuprian, which was a hideous windowed native cut before it was recut. It was probably the worst native cut of all time. It was recut, and while the recut is beautiful and the light return is excellent, you can tell it lost some saturation of color. Not a lot, but enough to notice. I''m still glad I recut it, and the cutter did an excellent job, but you can see a slight decrease in saturation of color. However, overall, it''s a more beautiful stone to me now, but I can see your point Chrono.

 

[PrecisionGem]

Any time a stone gets smaller, the depth of color can go down. If you are through 8 mm thick colored glass, and then compare that to 5 mm, it will look to have less color.

I guess my main argument is when you said "if the stone could have been cut better, it would." This just isn''t true. Rarely did the original cutter do the best possible job. Any stone could have been cut better. There is nothing attractive about a lop sided step cut stone with a window, which is what most sapphires are.
Even with a loss in size, the intensity of color can be increased with proper cutting. The polish certainly can be much better, and with the right design inclusions can be hidden.

I don''t do recuts of other people''s stone for the obvious reasons presented by the views in this thread. It''s not worth the hassle, and often it can take longer than cutting a rough stone from scratch. You spend a lot of time fishing round for a facet, and since the stones are seldom symmetrical, it only makes it harder.

There are guys who have made a living out of recutting stones, and are able to buy cut stones, re-cut them make them much more attractive and therefore sell them for 2 times the price of the original. Mediocrity is never expensive, and poorly cut stones are mediocre at best. A well cut stone adds rarity, and rarity is what increases value.

 

[LD]

From a consumer''s point of view .......... this is a Paraiba Tourmaline that I bought - fully aware of the hideous window. I did think I could live with it. I can''t. I''m pretty convinced that re-cutting would enhance the colour and return to the centre of the gemstone. Could I live with a smaller gemstone? Yes because it''s just sitting in a box and will never be worn otherwise! Will I take the risk of a re-cut? Yes because again, it will only sit in a box otherwise! What use is that?!

 

[T L]

Date: 7/30/2009 11:08:19 AM
Author: LovingDiamonds
From a consumer's point of view .......... this is a Paraiba Tourmaline that I bought - fully aware of the hideous window. I did think I could live with it. I can't. I'm pretty convinced that re-cutting would enhance the colour and return to the centre of the gemstone. Could I live with a smaller gemstone? Yes because it's just sitting in a box and will never be worn otherwise! Will I take the risk of a re-cut? Yes because again, it will only sit in a box otherwise! What use is that?!

Well LD
I think it's beautiul, and I would set it as is. You have seen my oval cuprian with the vivid color and the hideous window and the big inclusion across the table. Believe it or not, I get more compliments on that ring than my precision cut gems. Why? Because of the color. People don't see anything but vivid intense color.

Now, be careful if you do get that recut, because it might not be the same intense color as it is now after the recut. In fact, I feel that concave cuts generally do the best to retain color in a stone. I've noticed that with Anita's recut cuprian and Yingh's spessartite, but they were also very large stones to begin with. Recuts are still a risk you take, in particular if you're recutting a stone less than 3 carats.

 

[T L]

Date: 7/30/2009 10:59:10 AM
Author: PrecisionGem
Any time a stone gets smaller, the depth of color can go down. If you are through 8 mm thick colored glass, and then compare that to 5 mm, it will look to have less color.

I guess my main argument is when you said ''if the stone could have been cut better, it would.'' This just isn''t true. Rarely did the original cutter do the best possible job. Any stone could have been cut better. There is nothing attractive about a lop sided step cut stone with a window, which is what most sapphires are.
Even with a loss in size, the intensity of color can be increased with proper cutting. The polish certainly can be much better, and with the right design inclusions can be hidden.

I don''t do recuts of other people''s stone for the obvious reasons presented by the views in this thread. It''s not worth the hassle, and often it can take longer than cutting a rough stone from scratch. You spend a lot of time fishing round for a facet, and since the stones are seldom symmetrical, it only makes it harder.

There are guys who have made a living out of recutting stones, and are able to buy cut stones, re-cut them make them much more attractive and therefore sell them for 2 times the price of the original. Mediocrity is never expensive, and poorly cut stones are mediocre at best. A well cut stone adds rarity, and rarity is what increases value.

Well, if that''s the case, then there are lots of mediocre stones in the Tower of London!! LOL!!! I think a fine precision cut stone with poor color will be so much more mediocre than a stone with vivid rare color which is poorly cut. We can agree to disagree on this one Gene.

 

[chrono]

I am afraid I have to agree with TL on this one too. I’d rather take a poorly cut stone with great vivid colour over a precision cut stone with poor colour.

 

[LD]

I agree with you both but the window in this is really really really too big. The photo doesn''t do the colour of this stone any justice at all as it''s screaming neon (the photo above was taken through the perspex top of a gem box. If I put it on my hand, I can see my skin so clearly underneath. Ok, maybe a clever setting could hide it but .............

 

[T L]

Date: 7/30/2009 4:19:48 PM
Author: LovingDiamonds
I agree with you both but the window in this is really really really too big. The photo doesn't do the colour of this stone any justice at all as it's screaming neon (the photo above was taken through the perspex top of a gem box. If I put it on my hand, I can see my skin so clearly underneath. Ok, maybe a clever setting could hide it but .............

If it's super super neon and a rare color, I would be hesitant to recut it because loss of carat weight might also affect it's value. In some cases a recut can add value to an average color stone, but in terms of very valualble color, it might take away from it. You might also end up losing too much weight if the cutter encounters issues during the cutting process.

How large is the stone?

 

[LD]

4.1ct TL. So it''s a good size.

 

[T L]

Don't be surprised if you lose a carat or more off that stone in a recut though. In particular if it's shallow. I personally wouldn't cut it, because fine color trumps everything for me. I really love that stone, and I think it would look gorgeous set. That's just me though. You are the one that needs to be happy with it.

I apologize to the OP for hijacking the thread.

 

[PrecisionGem]

TL, we will have to agree to disagree. But I can tell you that the tourmaline pictured above if recut correctly, would have more intense color and sparkle.

I have seen in person the crown jewels in the Tower of London, and many of them have excellent cuts. 100 ct diamonds are not poorly cut, only the best cutters in the world are called upon to cut these stones.

As far as color over cut, are you are working on the assumption the well cut or precision cut stone are always of poor color, and native cut stones are good color? I don''t think this is true at all. Look at the aquamarine in my avitar. Pretty nice color, and it looks so good for two reason. 1. Its pretty darn nice color. 2. The cut is fantastic in brings this color out even more. If that same piece of rough had been a typical oval cut, with a step pavilion, and a window, it wouldn''t look anywhere near as good as it does, nor would it have sold for what it sold for.

My point is just this. All things being equal, a well cut stone will ALWAYS look better than a poor cut. Take a piece of rough, saw it half, have a typical native cut type cut on one, and a proper "precision" cut on the other, and I know that both you and Chrono would much rather have the well cut stone.

 

[T L]

Date: 7/30/2009 9:49:10 PM
Author: PrecisionGem
TL, we will have to agree to disagree. But I can tell you that the tourmaline pictured above if recut correctly, would have more intense color and sparkle.

I have seen in person the crown jewels in the Tower of London, and many of them have excellent cuts. 100 ct diamonds are not poorly cut, only the best cutters in the world are called upon to cut these stones.

As far as color over cut, are you are working on the assumption the well cut or precision cut stone are always of poor color, and native cut stones are good color? I don't think this is true at all. Look at the aquamarine in my avitar. Pretty nice color, and it looks so good for two reason. 1. Its pretty darn nice color. 2. The cut is fantastic in brings this color out even more. If that same piece of rough had been a typical oval cut, with a step pavilion, and a window, it wouldn't look anywhere near as good as it does, nor would it have sold for what it sold for.

My point is just this. All things being equal, a well cut stone will ALWAYS look better than a poor cut. Take a piece of rough, saw it half, have a typical native cut type cut on one, and a proper 'precision' cut on the other, and I know that both you and Chrono would much rather have the well cut stone.

Gene,
Well, when you said all poor cut stones are mediocre, I had to disagree because you left out the fact that there are fine colored stones that have poor cuts. The Black Prince's ruby (spinel) comes to mind when I think of such stones at the Tower of London, and let's say that there's a lot of very badly cut Columbian emeralds from Spanish shipwrecks, but I would take them.

. There are also some great cabachons which are not really faceted at all, but the color speaks volumes. I don't think any of these stones are mediocre by any stretch of the imagination.

As for performance, I would not recut my vivid oval tourmaline because I would be more worried about loss of saturation of color than the fact that it's precision cut. I'm also worried about that happening to LD's beautiful colored paraiba.

Now if we take that hypothetical situation where the gem was cut in half and had an okay native cut with more saturated color, and a great precision cut with less saturated color, I would take the native cut gem.
Now, all things being equal, if I had a great precision cut and an okay native cut, but the saturation of color was equal on both, I would take the precision cut gem. You are correct on that point there for me. I can't speak for Chrono.

The point I'm trying to make is that I don't believe that a gem will ALWAYS look better when precision cut. Is that the fault of the cutter, the material, I don't know for sure, but I just had to make that point so that people don't just go around thinking that a stone will automatically improve in color when recut.

Again, we must agree to disagree,

but I appreciate your argument.

It's a fun and interesting discussion.

We could continue this discussion in another thread. I feel terrible that we let the OP's thread get highly off the subject.

 

[chrono]

Date: 7/30/2009 4:19:48 PM
Author: LovingDiamonds
I agree with you both but the window in this is really really really too big. The photo doesn''t do the colour of this stone any justice at all as it''s screaming neon (the photo above was taken through the perspex top of a gem box. If I put it on my hand, I can see my skin so clearly underneath. Ok, maybe a clever setting could hide it but .............

This is a difficult situation. If very shallow, a complete recut might cost the stone at least 1 ct weight loss or more, which will also affect the value in a negative fashion due to excessive carat weight loss. Perhaps this one might be a good candidate for a partial recut (adjusting the pavilion angles only)?

 

[chrono]

Gene,
Of course if everything was equal with the exception of the cut, I will always choose the precision cut stone over a typical not so good native cut stone. However, I was responding to your statement of “poorly cut stones are mediocre at best”. I also think that not all native cut gemstones will be improved with a recut. Some might be a good candidate while others are best left alone. I do not have the knowledge and experience to see which one is which and some experienced cutters get stung by it too.

 

[PrecisionGem]

You are right, not all stones are good candidates for a re-cut. And this is one of the reasons buying a stone with the thought that you could have it recut is not always a smart thing to do. Having done so, would be as the President would say, "acted stupidly".

When I am in Tucson, I do casually look for nice colored sapphires that would be good candidates for a re-cut. It''s tough since most stone are to shallow, and the loss would be great on the re-cut.

The assumption that somehow the native cutter, know some secret to increase color, that a precision cutter doesn''t just isn''t true. It''s really the other way around. We model the stone in sophisticated ray trace software, and can see the brilliance, dispersion and depth of color change, as we slightly change the angles. And then we have the equipment to actually cut to these precise angles. Most of the stones coming from China, India etc. are cut by an assembly line process by teenagers in a sweat shop environment. Not much attention is paid to optimizing the beauty of the stone.

This isn''t to say that all stones cut overseas are bad. I have seen some very nice work done on this last trip to Africa, some very nice, well cut Tanzanites that I saw come to mind.

 

[LD]

Chrono/TL - The dimensions of the above stone are 11.00 x 9.00 x 6.00 so not particularly deep or shallow I don''t think. I''m prepared to lose carat weight to make this more beautiful (it deserves it)! The problem is finding (a) a cutter I have confidence in and (b) one that will take on the project - which is proving to be more difficult!

Gene just for clarification, I would never buy any stone thinking of a re-cut and certainly would agree that this is not a great way of buying gemstones. The colour of the gorgeous stone above blew me away and for the price I paid I thought I could live with the window. After living with it for sometime - and of course over time I''ve become much fussier as to what I will accept and what I won''t(!) - I''ve decided that the only course of action is a re-cut. After finding out how hard it is to find somebody to do it, I may have to accept that I will need to set it "as is" or just leave it loose and admire from afar.