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Kristen's Apex
by John Franke
USFG Masters Competition 2003
I cut this stone 11 mm and some what out of order of the published diagram
and will explain why. Most Master cutters have there own way of doing things and
I am no exception, so have at it your own way, this is how I did it.
I cut P1 to center point the best I could and then G1 & G2, you have to
split the corners by eye and I would do this move a little differently, I then
polished the girdle. Now I cut P2 and P5 at the same time meaning I cut 94-02
08-16 -22-26 and so on all the way around. The girdle line matched perfectly but
my center point was way off. 12-36-60-84 are the key facets and where 12 was
right on 36 came out a quarter inch high and the other two in between. So I re
cut 12-36-60-84 and then all others to meet point. That squared the stone up
nicely. Now I cut P3 and then P4 last to fit. I used 50,000 diamond on a tin
lead lap and used CZ as a material, you must use Beryl for the competition
stone. I knew I wasn't perfect on the first couple steps and would probably pay
for it on the crown.
I turned the stone over and with a 600 lap checked out my girdle line by
cutting it all the way around, this was easy as C1 and C2 are both 46.94 degrees
with a slight micro adjustment between the two. Every thing went together pretty
well I left out P8 and will cut that in last with the polishing lap, I then
repeated the above with a 1200 lap and sizing the girdle, I decided to square up
my Apex facets and over cut them a little and polish them now. I used a ceramic
with two hundred thousand on the apex and at five degrees still had some
difficulty keeping the lines straight. I started back with C1 and C2 to polish
up to the Apex. The only place I had any problems were cutting in two P8 facets
but I know that resulted from my not taking more time in the beginning. I spent
thirteen hours on this stone test cutting it, I would estimate a week to ten
days to do a creditable job on this. With 738 pattern points that puts the
degree of difficulty up there.
Co-Chair USFG Competition Committee
Art Kavan
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