Talk:Elser - Xtacy
XTACY - A New Design
When I started faceting, my instructor Hubert Heldner insisted we use natural stones. I'd expected to get a little square of sawn synthetic, but instead was taken to the rough box and helped to select a nice Danburite from the choices. Hubert's belief was that not only would working with natural stones help us learn to select rough and analyse shapes, but it would also encourage us to make a beautiful stone out of whatever nature handed us.
Somewhere on my pre-polish of the pavilion, I misindexed. Oops. I'm sure that with a synthetic, I'd have grabbed the 1200 and recut the thing but instead I called Hubert over. He looked carefully at the sad little unwanted facet and said "Yes, it's an error. Now make 7 more of them. It needs to be symmetrical and attractive." I did exactly that, and lost very little weight or time, and no face-up size. No one ever knew my Standard Round Brilliant wasn't quite so standard.
When I started cutting stones to sell those words "symmetrical and attractive" became words to live by. I carry inventory, which means I cut LOTS of stones in a year with no idea who might buy them. There isn't already a plan for where it will live so as long as it's pretty we're doing fine. 90% of the time, the stone has no problem becoming what I'd originally intended. Cut, polish, catalogue and have a coffee :-)
The other 10% of the time, and especially on expensive material where I want the absolute best yield, something crops up. An unexpected chip, an inclusion that was either hidden or just didn't seem as prominent in the rough, or the dreaded mistake on my part. Being able to stand back from a problem and reassess the design can be the difference between a profitable stone and one that sells for a loss.
Depending on where the problem is in the stone, the solution can be as simple as changing the angles a bit. As long as it stays above the critical angle, I find that changing all the angles by the same amount usually lets me finish the stone with good meets.
Other times, adding a tier of facets can work. It's especially nice if there's a problem right at the culet to cut a ring around the base. It reflects up nicely and looks like a feature, not a fix.
Reshaping the stone, usually by bringing in the corners can work but is a bit more difficult and requires good note taking along the way. Let's say I started with the Xtacy diagram by Tom Schlegel. The corners are cut 13 notches from the ends so 11-37 are each 13 notches off 24 and 59-85 are each 13 notches off 72. I can cut them 12 off or 11 off or 14 off and compensate for a missed index or a chip or just get a slightly wider stone instead of bringing the whole thing in to make those corners.
On this design, the pavillion isn't fussy. As long as I meet the girdle and the angles are good on tier 5 I'm home free. It's going to be a pretty stone. I can change the corners without a big impact.
Changing the corners can get tricky when I cut the crown, but it's usually not a big problem. The "last refuge of the faceter" is just to step the crown and avoid the whole meet point problem!
Is all that work worth it? Maybe not for an Amethyst, but absolutely for a Tsavorite.
For me, the faceting diagram is a visual aid and a great starting point, but understanding the geometry of the angles and indexes lets me make (usually) intelligent choices on the fly and fix problems as they happen. Julia Child once commented as she picked food off the floor 'No one knows what happens in your kitchen but you." No one knows what happens at my machine but me. If the stone is beautiful and the yield is good, then I've done my job no matter if the stone resembles my initial cutting plan or not!
Elser, Lisa., Silk Purses from Sow's Ear, http://ultratec-facet.com/Sometimes/some8-11.htm#LETTER.BLOCK8