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 Post subject: Re: How the American Faceting Technique Developed
PostPosted: Sat May 08, 2021 7:51 pm 
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True, I got it. That wouldn't be true meetpoint faceting would it?

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 Post subject: Re: How the American Faceting Technique Developed
PostPosted: Sat May 08, 2021 8:31 pm 
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Precision Gem wrote:
1bwana1 wrote:
Meet point faceting is that lapidary equivalent of strip mining and poaching. All waste precious natural resources.


I think that depends on the design you are cutting, not true for many designs. It can also be a function of the machine you are using. If you can very accurately control your depth of cut, then very often it isn't needed to cut to a center point.


I don't think it really depends as much on the machine you are using. More it depends on how you use it. If you use the machine to "set" the angles, and depth of cut, or if you use the machine to "measure" angles and depth of cut. Fundamentally different approaches to cutting.

As I understand it, the "American meet point faceting system" follows a specific work flow. This workflow follows the steps below.


Generally you dop the rough without preforming. This doesn't mean there has been no trimming on the rough.

You cut the pavilion first. - To me not a big deal, I can do it either way with the same results. I choose depending on the rough, the material, and the pattern being cut.

You cut a flat for the table, then dop to the table to cut the pavilion. Same as above to me.

You follow a pattern of angles, and indexes to cut to a meet point at the culet of the pavilion. This sets the size of the breaks, which in turn sets the size, L/W proportions, and outline of the stone when you cut the level girdle in. - The majority of the time, this is hugely wasteful of material.

You cut the rest of the pavilion facets in accordance with the diagram. Then transfer the stone to cut the crown.

You then cut the crown beaks at the same indexes as the pavilion breaks, and at the angle the diagram states. - This gives you a nice straight girdle line. It also ends up setting the crown height and tables size if you follow the recommended angle of subsequent rows. Once again, hugely wasteful.

Finally you cut in the table to meet the star facets properly.

The one time that I find this system appropriate is when you are cutting calibrated, matching stones. This will give you stones all sized the same, with matching proportions in all directions including table size. This is the primary reason that even well selected stone parcels cut calibrated almost always result in a 20% yield +- just a few percent.

The meet point approach has a different order of priority that traditional stone cutting. It tends to give more weight to brilliance, and pattern. Where as traditions cutting handles most issues when the preforming is done. The shape L/W, and bulge (and therefor angles), are all set during preforming. The facets are then laid on the preform.

It is worth noting that in most American style cutting the mast height (or platform/whatever) is used to control depth of cut and therefore symmetry. Since this depends on distance from the center of the dop to be accurate, and off center when doping results in excess material loss. The traditional cutters do not depend on centering on the dop. The are constantly adjust angle and mast height to accommodate this. Even on matching sets of facets in a tier. This is one of the primary drivers of the traditions mixed cut faceting style. The step cut pavilion offers the most flexibility in matching the rough and cut. Just go take a look at the the expensive stones in the World. Except for s few specialty categories, the vast majority of winners in the major AGTA Spectrum Awards also employ this style. The vast majority employ this style, or a Portuguese based style. Most with keels, not pointed culets.

It should also be noted that traditional cutting can also be very precise with excellent meet points, symmetry, proportions and polish.

It should also be noted that many who practice the basic workflow of meet point faceting modify certain aspects to achieve better control of color, inclusions, and yield.


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 Post subject: Re: How the American Faceting Technique Developed
PostPosted: Sat May 08, 2021 8:33 pm 
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glhays wrote:
True, I got it. That wouldn't be true meetpoint faceting would it?



Agree, or at least a modified version of it as I posted above.


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 Post subject: Re: How the American Faceting Technique Developed
PostPosted: Sat May 08, 2021 10:51 pm 
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I don't want to debate the methods of cutting on this thread in detail, I think it's a bit off topic, and we have done this a few times before anyway.

But I think Steve when you say "hugely wasteful", that that is hugely over stated. I find from posts you made in the past that my typical yields are very close to yours, maybe a touch less. But I think I am cutting maybe faster. I am not writing down angles and indexes to find them again when polishing, or spending a lot of time on preforming. For most stones, I am cutting in 1 to 1.75 hours. So for me, time is important, and if I get a stone with perfect symmetry and proportions that performs great but weighs 2.4 cts. vs a stone that looks like most every other native cut stone but weights 2.6 cts. it's not an issue. Instead of the 2.6 ct at $250 per ct. I'll sell the 2.4 ct stone at $300 per ct.
I cut for money, not for weight.

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 Post subject: Re: How the American Faceting Technique Developed
PostPosted: Sat May 08, 2021 11:02 pm 
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So in this hugely debatable topic where did we begin? Precisely exact measurements of rough? 2.4 vs. 2.6 final cut gems with a margin of $50 per carat doesn't equate to a hugely big amount to squabble over even if it is about time spent. I asked that same question of JKP directly on topic so it is somewhat on topic.

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 Post subject: Re: How the American Faceting Technique Developed
PostPosted: Sun May 09, 2021 2:56 am 
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True, but 2.4 vs. 2.6 final cut gems on a $3000/ct emerald is quite a bit different right? :lol: Since last year, the majority of cutting work I'm taking on is emeralds so these little bits are becoming more noticeable to me.

But aside from all that, I didn't mean this post or video to start a battle between meet point and traditional cutting. They are both valid but they have different goals. Currently I am very interested in the development of the American style just for the sake of the interesting history.

In my research powerpoint for my American history book I currently have 459 references/photos/article/etc (just for 1840-1950) and I have 20 pre-1940s books and magazines arriving tomorrow with lots more data points. Very exciting to see how this all unfolds. Currently no one knows the true origin of mast machines but I am very very close to connecting all the dots back to the 1880s.

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 Post subject: Re: How the American Faceting Technique Developed
PostPosted: Sun May 09, 2021 12:34 pm 
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Justin, I think that a good review of American faceting should include Jeff Graham and Jon of Gearloose. Both have contributed greatly to many cutters. I don't think you have been cutting long enough to remember Jeff, he passed away before you started cutting, but his website and tutorials provide a lot of information to help cutters. His views were no doubt very strong, and he could at times be argumentative but a lot of people who started cutting 20 or more years ago gained much from him.

Gearloose I think has simplified polishing for many people, and turned it from a witchcraft into something quick and easy. Although his products are used all over the world now, they got their roots in American cutters.

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 Post subject: Re: How the American Faceting Technique Developed
PostPosted: Sun May 09, 2021 3:05 pm 
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My earlier point exactly about Hoffman and Graves. Also no mention of Van Sant and his early contributions. My interest in this now wonders if the GIA library has any litature that might point to the correct data. Jon may know this himself, he has vast knowledge of this arena we all love.

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 Post subject: Re: How the American Faceting Technique Developed
PostPosted: Sun May 09, 2021 3:42 pm 
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Precision Gem wrote:
Justin, I think that a good review of American faceting should include Jeff Graham and Jon of Gearloose. Both have contributed greatly to many cutters. I don't think you have been cutting long enough to remember Jeff, he passed away before you started cutting, but his website and tutorials provide a lot of information to help cutters. His views were no doubt very strong, and he could at times be argumentative but a lot of people who started cutting 20 or more years ago gained much from him.

Gearloose I think has simplified polishing for many people, and turned it from a witchcraft into something quick and easy. Although his products are used all over the world now, they got their roots in American cutters.


Excellent suggestions for additional influential sources of information.


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 Post subject: Re: How the American Faceting Technique Developed
PostPosted: Sun May 09, 2021 8:42 pm 
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Don’t worry. Van Sant is going to get some decent airtime in a documentary I’m currently working on about the history of design software. As for Jeff Graham, his work also got some airtime in my video about the opposed bar cut. I interviewed gearloose as well as Adamas when I was working on an article about the history of laps and polishing a few years back which is now getting published in the next issue of the Italian Gemmological Review.

The story is epic but I promise not to forget anyone. I don’t have any near plans on the modern american history though. Currently focused on an American history book 1880-1940 which I hope to release next year and an overview of the entire faceting story 1400-1900 which if I can get it done might also come out next year. I have a lot of books brewing inside me right now!

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