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 Post subject: I need some help for a facet design for a pear design.
PostPosted: Sun Dec 13, 2009 3:42 pm 
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I have a pear tourmaline stone 10.42mm x 15.83mm. I need to recut the table and crown facets. I can't find a design to use. Can someone provide me with a suitable design to be able to recut this stone.
Thanks in advance for you help. :D

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PostPosted: Sun Dec 13, 2009 5:21 pm 
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Location: Washington State
How much depth do you have to work with ? Any pictures of the stone ?

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 Post subject: The depth is 6.34mm
PostPosted: Sun Dec 13, 2009 5:46 pm 
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The depth is 6.34mm, I'm hoping to just cut the table and the facets and maybe the girdle.
Here is a picture.
Image

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PostPosted: Sun Dec 13, 2009 8:56 pm 
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Am I correct, that if you recut the girdle, you will affect many of the pavilion facets as well? Maybe you want to leave the girdle alone, and just recut just the crown.

Though from the photo, I can't tell if the girdle is damaged, or uneven. Unless it was damaged, I wouldn't mess with it.

This is just my inexperienced opinion.

Kelley


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PostPosted: Sun Dec 13, 2009 11:12 pm 
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Nice color ! Is that a crack up towards the left side of the tip ? Most pear shapes have a pretty standard crown, but it would need too be adjusted for crown height or angles that you have available. If no one else chimes in with a link or something you can always send me an e-mail and I'll send you a typical crown for a 1.5 aspect ratio pear shape and if the angles are too steep I can change them a bit. I wouldn't re-cut the girdle unless it's dinged or too shallow. My address is michael@gemshoppe.com if you want a diagram.

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 Post subject: You both are correct!
PostPosted: Sun Dec 13, 2009 11:24 pm 
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I don't want to change the girdle, it's current thickness is 0.85mm which is the best I could measure. The table surface to the top of the girdle edge is 1.3mm in height. Looking at the picture you will see a sparkle half way up on the right side of the table, that is where the problem lies. I would have to drop the table surface or change the angle of the facets to correct the flaw. There are some scratches on the table. That is the only flaw on the crown, the other sparkle is from the lighting.
Thanks for your comments.

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 Post subject: Tourmaline recut
PostPosted: Mon Dec 14, 2009 2:56 am 
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Vetman;

I'm wondering how much cutting experience you have had? From your demensions I'm guessing your stone is in the 6ct range? Your biggest problem here will be dopping up the stone accurately. Also, can you tell how much material do you need to remove to clear the flaw? If the flaw is not too deep a recut of the crown, changing the angles on your main and star facets to match up to the table would do. I would map the design on the table and use the same design to recut. This would give you the least amount of loss due to the recut. I don't have a lot of cutting experience (3.5 yrs.) but have done my share of recuts. Recutting a small amount off the table alone has worked well but of course your meet points on your star facets will be gone. With a 6 ct. stone a total recut might be the best route. As I said, dopping up the stone keeping the girdle level all around with the culet centered is not an easy task. If you have the experience to do that then recut the crown with the same cut you have. Pick any 16 sided or 12 sided design (I'm assuming it's one of these) to estimate the angles on your main facets. You might want to rough in (or polish) your table first to make sure you will lose the flaw. I think you will lose 1-2 ct in an total recut of the crown and pavilion. Hope this helps, bob


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 Post subject: Re: tourmaline recut
PostPosted: Mon Dec 14, 2009 3:19 am 
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Vetman;
In reading your previous post I noticed your crown height at 1.3 mm. Seems a little shallow to me. If your girdle is at about .85mm then the height of your crown is only 1.5X the girdle thickness. Is that crown height correct? If so, you have a large belly cut native stone and I would recut the whole stone. Again, hope this helps. bob


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