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 Post subject: Starbrite cut
PostPosted: Thu Apr 04, 2019 11:00 pm 
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I have seen some pictures of commercial gems both round and square (cushion) shapes which say Starbrite cut. I have searched high and low for a faceting diagram but cannot find one.

Does anyone have faceting diagram for a Starbrite cut, or point me to a link for one?

Thanks.


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 Post subject: Re: Starbrite cut
PostPosted: Thu Apr 04, 2019 11:18 pm 
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I think that is a "Fantasy" cut (concave faceted) cut that has been Trademarked possibly by John Dryer as he seems to be the only one showing stones use this name. You might try contacting him to see if he will allow non commercial use. he is a nice guy.

https://www.johndyergems.com/index.html


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 Post subject: Re: Starbrite cut
PostPosted: Thu Apr 04, 2019 11:55 pm 
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1bwana1 wrote:
I think that is a "Fantasy" cut (concave faceted) cut that has been Trademarked possibly by John Dryer as he seems to be the only one showing stones use this name. You might try contacting him to see if he will allow non commercial use. he is a nice guy.

https://www.johndyergems.com/index.html


Yes, that's where I saw it. I never noticed the TM at the end, either... so I guess it is trademarked.
Also, did not think they were concave faceted... so it is out of my league for now.

But, thanks a lot for the information!


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 Post subject: Re: Starbrite cut
PostPosted: Fri Apr 05, 2019 9:52 am 
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The trademark means that you can't use the name, not that you can't cut one. It does look like a fantasy cut, though.


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 Post subject: Re: Starbrite cut
PostPosted: Sat Apr 06, 2019 3:40 am 
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AlBalmer wrote:
The trademark means that you can't use the name, not that you can't cut one. It does look like a fantasy cut, though.


Cool... did not know that.

I really like how the Ametrine pieces show up with this cut. You can clearly see the line of demarcation between citrine and amethyst sections. I cut an ametrine in SRB and all one sees is an overall yellowish effect to the amethyst coloration. I can only see the line of demarcation when the stone is tilted at a particular angle.


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 Post subject: Re: Starbrite cut
PostPosted: Sat Apr 06, 2019 10:29 am 
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When cutting a stone to show bi-color the SRB, or any "brilliant" facet pattern is not a good choice. The Brilliant facet pattern blends colors as you have discovered. This is very useful when dealing with zoned colors in stones and makes them look even. It is best to use a step cut pattern for bi-color stones.

In Ametrine there are two basic zoning patterns one normally see in the rough. One has 4 approximately equal sized,pie shaped, zones coming together in the center of the stone. The other has a straight line division between the color zones, hopefully dividing the stone into two equal sized color zones. These two types should be handled differently. Which of these did you have in your stone.


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 Post subject: Re: Starbrite cut
PostPosted: Sun Apr 07, 2019 5:38 pm 
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1bwana1 wrote:
When cutting a stone to show bi-color the SRB, or any "brilliant" facet pattern is not a good choice. The Brilliant facet pattern blends colors as you have discovered. This is very useful when dealing with zoned colors in stones and makes them look even. It is best to use a step cut pattern for bi-color stones.

In Ametrine there are two basic zoning patterns one normally see in the rough. One has 4 approximately equal sized,pie shaped, zones coming together in the center of the stone. The other has a straight line division between the color zones, hopefully dividing the stone into two equal sized color zones. These two types should be handled differently. Which of these did you have in your stone.


The Ametrine piece I cut has a straight line division between the color zones.
When viewed at a particular angle you can see the two zones as seen below:

Image

I tried to get a good picture of the coloration from the top but finding it very tough... Here is the best I could do:

Image

Kinda hard to tell that it is a bi-color ametrine piece at a casual glance, though it has a lot of brilliance.
What are some of the best cuts to use for bi-color stones like these?

Thanks.


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 Post subject: Re: Starbrite cut
PostPosted: Sun Apr 07, 2019 8:00 pm 
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Emerald cuts, ovals, and rectangular cuts in cushion, radiants will show the bi colors the best. RBC is probably one of the worst as you have discovered.


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 Post subject: Re: Starbrite cut
PostPosted: Sun Apr 07, 2019 11:37 pm 
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Thanks 1bwana1, I have a few similar ametrine pieces. Will try some of the cuts you mentioned.


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