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I have a Sapphire preformed for a Robert Long design

Ember - 4.037 and am confused with reverse pav/crown angles and sequence - the angles and sequence go higher cutting the girdle away - seems like this December 1980 The Faceter’s Gem Vol 14 page 22 got scrambled - anyone seen this before?

Hello. Well … it’s hard to judge anything without seeing a photo, and it is desirable to have a high-quality and clear one.

The question is about a design sequence; pavilion
PF1 36.5 = 4 corners PF 2 = 38.0 2 ends PF 3 43.1 = sides L/W 1.20 96 index then…

Then 8 corners PF 4 - 5 - 6 @ 90 = girdle … done.

But here is where I get confused - P1 46.9 P2 69.0 P3 52.0 all same corners as PF1-2-3 - then - P4 47.0 P5 45.6 P6 46.3 P7 52.0 P8 43.0 - PF1 & P3 are all 8 corners - 4567 are mains and 8 to C.

These numbers tell me the girdle is cut down?

This is an emerald brilliant by Robert Long in 1980.

Yes, the girdle will be lowered going from the preform to the actual pavilion steps. Ember is a nice design and one of favorites. The instructions look complicated, but following them flows nicely. Good luck.

Thanks Mr. Azeller - I have a piece of junk amethyst almost ready to cut following the steps as they are on the pattern - odd that the 90 degree girdle angles are cut away - I’m not getting that in my old brain but maybe the test piece will make sense of it - appreciate your kind reply.

Have you had a chance to cut your amethyst yet? How did it go?

Frustrated - it fell apart - junk - I’m moving on to a round in citrine leaving the sapphire aside until I get more skill at visualizing the design and steps.

Amethyst is not my lucky material - almost all I have worked is washed out if it is clean or falls apart if it has color.


Well if you get to try this design out on something more stable please let us know.

And I know you can get synthetic amethyst that is probably totally perfect and won’t crumble, but I don’t know if you’re interested in messing with that kind of stuff.

In Tom Herbst’s book Amateur Gemstone Faceting he suggests using beryl as a practice stone due to it being inexpensive but also teaching you how to work emerald and other more expensive varieties like aquamarine at the same time. Also the stones you end up with will most likely be worth much more in natural beryl than in synthetics or quartz stones.

I have only done quartz and some synthetic corundum on a friend’s machine, but I am waiting on mine now and plan to use natural beryl and natural white sapphire when it gets here.

Thank you, I have Tom Herbsts books - volumes of answers looking for someone to understand - love it - will try that design again in something BIG to see the process through without worrying about watching it get eaten up in those early steps - thanks Colin.