A New Design
XTASY CUT by Tom Schlegel -- Click to View
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
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
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
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
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!
The Xtasy Diagram