Ballgame by Jack Rowland

Ballgame (ballgame.gem)
Angles worked out on GemCad by Jack RowlandFor RI Sapphire and Up
Angles for R.I. = 1.73 49 facets + 16 facets on girdle = 65
4-fold, mirror-image symmetry 64 index
L/W = 1.000 T/W = 0.597 T/L = 0.597 P/W = 0.435 C/W = 0.141
H/W = (P+C)/W+0.02 = 0.596 P/H = 0.730 C/H = 0.237
Vol./W^3 = 0.230

Pavilion
W1 41.50 01-15-17-31-33-47-49-63 Cut to temporary center point (TCP)
W2 39.00 06-10-22-26-38-42-54-58 Cut to TCP
G1 90.00 06-10-22-26-38-42-54-58 Cut girdle, leave about 1/3 for crown
G2 90.00 01-15-17-31-33-47-49-63 Level girdle all around
C 41.00 64-16-32-48 Cut to girdle meet - See note 1
Note 1- These facets cut very fast. Use slow speed and only with fine lap. Polish in the meets.
Crown
B1 38.00 01-15-17-31-33-47-49-63 Leave some girdle
B2 33.50 06-10-22-26-38-42-54-58 Level girdle
M1 35.00 64-16-32-48 Cut to girdle-B1 meet
M2 29.50 08-24-40-56 Cut to girdle b2-meet- see note 2
S 23.00 08-24-40-56 Cut to M1-M2-B1-B2 meet
T 0.00 Table Cut table to proper width for S
Note 2- May need some fine angle adjustment to make the M1-B1-B2 meet.

I designed this cut during the baseball strike of 1994. I was in one of those "take me out to the ballgame" moods. I think Baseball should consider this for their World Series Rings.

This is an outgrowth or variation on a theme from "Boxes". You'll see it has the same sort of outline and general feel. Save this cut for higher RI material such as sapphire, garnet, zircon, etc. Lower RI material just doesn't sparkle well with this cut. One thing I have noticed is that if you do cut this with low RI material such as quartz or apatite, you can see the diamond pattern. It all but disappears in the higher RI gems.

Only a few words of caution on this cut. The C facet in the pavilion cuts very fast. Use only slow speed and wait until the fine lap to cut it. Don't cut all the way to the meet point. Polish the meet in or it will overcut. Polish this facet last.

The M2 crown facet also needs a little attention. You may need to make some minor angle adjustments to get both the girdle and crown meets to come in. No big deal, just keep it in mind.

If you are looking for a very dramatic cut-corner square cushion, this could be the one for you!


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