Talk:Akhavan - Elser's Challenge

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This design was written for a 9.15 carat, bubblegum-pink tourmaline crystal that Lisa Elser helped me pick out in Tucson (she was acting as my newbie guide for the day, teaching me how to evaluate rough). Oddly enough, this crystal was shaped with a short A, extremely long B, and short C, so the general shape was that of an absurdly stretched hexagon looking down the C-axis. After removing flaws and rind, the ideal yield was an oval with a L/W of about 2.1. She was joking around that I didn't have GemCAD yet, and I mentioned that I probably wasn't skilled enough to cut this stone yet. Eventually it got down to joking about who could pull the biggest yield, and she issued a challenge that I wouldn't be able to pull more than 2 carats for yield, and that I'd probably have to trim the stone down a lot and use a pre-existing barion pattern.

Well, I win. (I hope. Haven't cut it yet.)

As with all keeled ovals/marquises with high L/W ratios, the center has a simple, standard reflection pattern with high light return, while the corners have an intense reflection effect with extremely high scintillation and color deepening. I tried to get this effect to blend together as much as possible - if you want to do that, scale the crown up by 1.18 and the pavilion deeper by 1.05. If you leave it as is, you'll get the rendering.

The design works in RIs from beryl to CZ (RI = 1.56 - 2.16) with no changes. I definitely do NOT recommend any materials with a lower RI (so no feldspars or fluorites). If you cut this in something with high dispersion, you'll get a little distracted in the corners - in my opinion, it looks gaudy, but some customers might enjoy the effect.

Now...I hate ovals. So I was completely expecting this to turn out unreasonably difficult and/or time consuming. Well, it looks like that's how it turned out. There are six complex meets on the crown, but thankfully no problematic codependent meets. The pavilion requires a LOT of angle changes, but I couldn't figure out a better way to generate the outline other than a preform, and that would make me lose too much off the rough.

Difficulty level = low expert (well, crap, I can't cut this yet)