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 Post subject: Where are the high-end traditional faceting designs?
PostPosted: Sun Apr 22, 2007 5:33 pm 
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I've been faceting for a couple of years now, and have lots of designs(Long & Steele, Jeff Graham, Vargas, etc), but I would consider most of these "fancy" cuts. I have not seen many designs for cushion, oval or pear shapes that I keep seeing in the high-end jewelry magazines or websites like the following.

http://www.multicolour.com/detail/?/det ... &930512007
http://www.multicolour.com/detail/?/det ... &930512007
http://www.multicolour.com/detail/?/det ... &930512007

These appear to have pavilions cut with a "native" cut (lots of pavilion facets in several tiers, almost like a Portuguese cut). I understand that the overall performance is probably not as good as a brilliant cut pavilion, but frankly I am partial to "sparkly" stones and I think they look more traditional.

So the question is - are these trade secrets or are most hobby faceters interested in the newer fancy cuts?

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Gary


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PostPosted: Sun Apr 22, 2007 10:27 pm 
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All of those gems along with the "native" cuts look to me like a regular crown (Brilliant, scissor, etc) with just a step cut on the bottom.

Can't say I've ever been a fan of the step cut bottom, the pavillion angles are all over the place and it's hard to predict the internal reflection. I guess if you're using that a step cut for color (like in emeralds) it's probably OK but I just think it looks like a stone that someone slapped a few facets on the bottom to finish it.

I can also see them doing it for weight because they can have a big "belly" on the stone too and preserve weight. Again, I'm not a huge fan of cutting that style.

One of the reasons I started faceting was to cut something different, so yes I would be interested in cutting more of the "fancy cuts". Besides, I always thought that if I wanted a "traditional" cut, I could send it out and have someone do it for 30% of what it costs me to do.


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PostPosted: Mon Apr 23, 2007 11:06 am 
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I probably should have been more specific. I am not looking to recreate a cheap native cuts with the deep bellies and the mishappen facet locations. I'm looking for optimized designs for ovals, pears and rectangular cushions with good performance that have several tiers of pavilion facets - similar to a Portuguese cut in a round. I've seen nice stones in high-end jewelry and in stones coming from Idar-Oberstein, so there is obviously some demand for a well-cut "traditional" stone.

Thanks,
Gary


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 Post subject: Cuts
PostPosted: Mon Apr 23, 2007 11:59 am 
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One of the problems that arrises when you have many tiers of facets is the last tier or 2 ends up under the critical angle and the stone windows. I think if you look at most of the stones on the Thai websites such as Mulitcolor you will see the stones are windowed. The other issue is, I'm guessing you are cutting on a mast head faceting machine, and doing meet point cutting, these designs are more of a freeform cutting. Another reason why the rounds are not really round, and the ovals are lopsided. To cut an oval, with a stepped pavilion with many tiers of facets, I don't think you woud be cutting anything to a center point except for the last set of facets. So you would have to eye ball in the shape, or cut a preform.

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PostPosted: Fri Apr 27, 2007 10:04 pm 
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Rocketgems,

I think that you have things backwards, way way backwards. Those cuts you view as traditional most everyone views as "commercial". As Precision Gem and others have posted, they are cut to maximize weight (stones are sold by $$$ per carat) and little attention is diverted to appearance.

The Standard Round Brilliant (SRB) is the standard cut for diamonds, that by which the other cuts are measured. A brilliant pavilion will give a very sparkly stone, while commercial cut stones with levels of square facets will usually not, what with windows, etc. to distract from the stone. A brilliant pavilion design is most definitely NOT a 'fancy' cut.

As you have many designs available to you, consider that probably 100% will NOT cut a windowed stone, though it is possible that a Long and Steel design could if it is stretching a particular shape out too much. (Yes, I do have the complete set of L&S, as well as all of Jeff Graham as well as 500 plus other designs to work with.)

If you MUST cut such a stone, look at a Jeff Graham design for sapphires:
http://www.faceters.com/designs/ad7/mc64.shtml .

Most folks view the commercial type stones by another name (besides lousy) -- Rough, something from which to cut a good stone.

Some folks make a career out of recutting those 'native' cut stones.

I have to say that I cannot recall another time when someone preferred a native cut over a precision cut...

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PostPosted: Sat Apr 28, 2007 12:26 pm 
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Let me try this again...

I am NOT looking to recreate a native cut, nor do I prefer a native cut. All I'm looking for were classic designs that happen to have a lot of facets. If you look at the winners of the AGTA cutting awards, you'll see what I mean. I consider these to be "classic" designs (pears, cushions, ovals mostly). You may consider them native cuts, but I don't - and I don't think those winners would either!


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PostPosted: Sat Apr 28, 2007 1:46 pm 
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A bit on the side:

Assuming someone would cut that step pavilion & brilliant-ish crown (=the dreaded 'native' recipe) to some right angles. Is there no hope for the design?


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PostPosted: Sat Apr 28, 2007 10:46 pm 
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Assuming someone would cut that step pavilion & brilliant-ish crown (=the dreaded 'native' recipe) to some right angles. Is there no hope for the design?


Definitely, I don't think we're saying that there's not hope for the designs. I think, as PG mentioned, what tends to happen is the last tier or two ends up being below the critical angle and there is some windowing. I think you could easily alter the angles to make the cut look good, it just never seems to happen in "native cuts" because it's usually about weight. I think if you look at Jeff Graham's site for the sapphire cuts (PG's post) you can see how it should be done, again, it just never seems to get done.

I think rocketgems' posts are good in that he(she?) is looking at overall brilliance and appearance of a stone, and the "style of cut" is secondary. I think more of that should happen when looking at cuts. Having said that, I think meetpoint faceting where you can design the angles and somewhat predict the reflections in the stone, tend to produce better results then just cutting a few tiers of pavillion facets on a stone.


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PostPosted: Sat Apr 28, 2007 10:47 pm 
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Rocketgems,

The fellow who taught me faceting (Matt) is one of the winners you talk about, both Spectrum and Gemmies. His stones have been on the covers oc Colored Stone, Lapidary Journal and others.

I, and most other folks, cannot duplicate what he does as he is wonderfully talented, but he cuts NOTHING in what you want to call 'Classic" designs. For example, his winning (second place) entry is three citrines and an amethyst cut in unusual cuts and glued together. He and I talked about and went over the set of stones about a month ago when he got them back.

Or take a look at Dale Hargrave who came in first and second in multiple categories in the Spectrum awards. His stones are largely carved and concave faceted. They, also, are works of art. They are not 'traditional' or 'classical'. It's kind of like saying Van Gogh painted traditional/classical landscapes.

If you want to cut designs with more common shapes and with lots of facets, take a look at Jeff Grahams Addition # 12, his Glitter designs. Only 4 out of 40 or so have fewer than 100 facets. I test cut the design Fancy in clear quartz and it is really remarkable, but a lot of work, with all those facets! Something easier to polish would be a good idea.

You said you have Jeff's designs. If so, you already have what you are looking for.

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PostPosted: Sat Apr 28, 2007 11:01 pm 
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ars is correct that the 'native' pavillion can be done correctly -- but one must put correct angles over weight retention. In general, that style of pavilion is not as bright as a 'brilliant' pavilion, which is why the 'brilliant' is called brilliant.

However, there are non brilliant designs that are just as bright as brilliant designs, given the overall design and the interplay between the pavilion and the crown facets, plus the table type and size.

There is a software program called GEMCAD which lets you do cut design and calculates the resultant brilliance, both straight up (perpendicular to the table) and tilt angle -- 10 or so degrees off of perpendicular. You can try things out, see what the effects of angle changes are, etc.

However, a major problem is that the calculations assume a clear, colorless stone. In the real world, if you are cutting a colored stone (that is not clear/white) then the color itself affects the brilliance by absorbing light. The more it bounces around through the stone, the greater the absorption. For example, consider a light blue sapphire, a ceylon blue sapphire and a "royal blue" (almost black it's so dark) sapphire, all cut in the same design, hence the same theoretical brilliance. Do they look the same?

So brightness is a significant factor, but with colored stones it is far from the only factor.

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PostPosted: Sun Apr 29, 2007 7:28 am 
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AGTA has a Classic Gemstone section, is that what you are talking about when you were referring to their awards, Rocketgems?


Facetor wrote:
There is a software program called GEMCAD which lets you do cut design ... [...] However, a major problem is that the calculations assume a clear, colorless stone.


DiamCalc adds color. There might be others that do too, just don't know them. Neil has it too. (LINK to thread where it was talked about a bit, see the 'spinel cubes' on the first page)


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PostPosted: Sun Apr 29, 2007 12:35 pm 
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Yes, I'm looking at the classic faceting design competitions in AGTA. Some (but not all) of the stones by John Dyer, David Clay, and Allen Kleiman have what appear to be more pavilion facets than a standard brilliant cut. Of course, they are cutting huge natural stones and therefore have the room for additional facets!


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PostPosted: Sun Apr 29, 2007 2:29 pm 
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rocketgems wrote:
Yes, I'm looking at the classic faceting design competitions in AGTA. Some (but not all) of the stones by John Dyer, David Clay, and Allen Kleiman have what appear to be more pavilion facets than a standard brilliant cut. Of course, they are cutting huge natural stones and therefore have the room for additional facets!


Hi Rocket. Some faceters call the technique "cutting to the crystal" and they invent designs on the fly to conform to the natural crystal shape for maximum yield. They know enough about gem optics to ensure good weight retention, a pleasing shape, symmetry and light return.

It's pretty obvious to me those were the considerations in cutting the stones in the value range you referenced. When you're cutting rough with the potential to bring $200,000, you're not going to waste a point of weight.

Several Brazilian cutters I know use jamb-peg machines built after designs originally developed in Idar-Oberstein, Germany. Germans in Brazil exploited the gem deposits there starting well over a century ago. They brought their own equipment and taught their faceting methods to Brazilians.

The technique involves very careful preforming, usually with a bit of a "midriff-bulge" below the girdle for weight-retention. The culet facets are usually designed above the critical angle for good face-up brilliance but most production stones exhibit tilt-windowing quite easily. They usually use trianglar (brilliant) facets on both pavilion and crown. These cutters are familiar with critical angle faceting and can produce very brilliant stones.

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PostPosted: Sun Apr 29, 2007 3:45 pm 
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Chances are I am wrong but...

... with HUGE stones and very carefully set up pictures, couldn't it be the case that internal reflections might be making those stones look as if they had allot more facets then they do?

Which isn't saying that they do not have more than the basic brilliant or whatever (again, something I would expect on a large stone).


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PostPosted: Mon Apr 30, 2007 11:12 am 
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valeria102,

Actually the design itself can have few facets and appear like it has a lot. And size really isn't important, other than if you want to cut 100 plus facets, you need enough stone to fit them all in, as well as when facets get too small, it's hard to see them. I once cut a SRB with 32 pavilion mains (no breaks) just to see what it looked like and the effect was underwhelming. Looked much better with 16.

Jeff Graham has two books of such designs which he calls Mirage.

Or you can look at really simple designs, such as:

http://www.faceters.com/designs/ad4/mc4.shtml

or:

http://www.faceters.com/designs/ad4/mc41.shtml

or:

http://www.faceters.com/designs/ad4/mc8.shtml

or:

http://www.faceters.com/designs/ad4/mc7.shtml

Where the visual interplay of the crown and pavilion facets cause the appearance of many more facets than there actually are.

Note the numbers of actual facets in the above designs, 20, 21, 30 and 43. There are also some designs by Dan Clayton and John Bailey available on the Web that have this effect.

The point here is that while a design can have many many actual facets and look like that, a knowledgeable designer can achieve similar effects with far fewer facets, if they want to.

Fewer facets = less time = time is money spent = more cut stones per time unit. If one is cutting for competition, then time is a non-factor so one can cut as many facets as one wants to. I know a couple folks who spend 200 hours plus (that's all they will admit to) on their "competition stone" but about 2-4 hours normally when cutting a stone.

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