|Sonoran Snowflake - designed by Jeff R. Graham firstname.lastname@example.org ©1998|
|Angles for R.I. = 1.62||163 facets + 18 facets on girdle = 181|
|6-fold, mirror-image symmetry||96 index|
|L/W = 1.098 T/W = 0.897 T/L = 0.817||H/W = 0.787|
|Vol./W^3 = 0.373||Brightness at 0 degrees tilt for R.I. = 1.62
COS = 73.8 ISO = 81.5
|P2(G)||90.00||04-12-20-28-36-44-52-60-68-76-84-92||Cut a level girdle, meet P1.|
|P1||54.97||04-12-20-28-36-44-52-60-68-76-84-92||Cut to centerpoint.|
|P3||48.10||04-12-20-28-36-44-52-60-68-76-84-92||Cut a step to about 15% of girdle.|
|P4||44.09||04-12-20-28-36-44-52-60-68-76-84-92||Cut step to about 50% of girdle.|
|P5||49.09||96-16-32-48-64-80||Cut to meet girdle.|
|P6||46.11||03-13-19-29-35-45-51-61-67-77-83-93||Cut to meet P1, P3, P5.|
|P7||42.07||96-16-32-48-64-80||Cut to meet P5, P6.|
|P8||46.11||04-12-20-28-36-44-52-60-68-76-84-92||Cut step to about 25% of girdle.|
|P9||41.45||04-12-20-28-36-44-52-60-68-76-84-92||Cut step to about 60% of girdle.|
|P10||39.00||04-12-20-28-36-44-52-60-68-76-84-92||Cut to about 25%...|
|P11||60.72||08-24-40-56-72-88||Cut in until they look right...|
|P12(G)||90.00||08-24-40-56-72-88||Cut to meet girdle, P11.|
|C1||78.00||08-24-40-56-72-88||Cut to meet girdle.|
|C2||84.00||96-16-32-48-64-80||Cut to meet P5, NO GIRDLE.|
|C3||76.00||07-09-23-25-39-41-55-57-71-73-87-89||Cut to meet C1, girdle.|
|C4||68.00||06-10-22-26-38-42-54-58-70-74-86-90||Cut to just make C2 diamond.|
|C5||64.00||07-09-23-25-39-41-55-57-71-73-87-89||Cut to meet C1, C3.|
|C6||58.00||96-16-32-48-64-80||Cut to meet C2, C3.|
|C7||49.98||08-24-40-56-72-88||Cut to meet C1, C3, C5.|
|T||0.00||Table||Cut to meet C5, C6.|
|Sonoran Snowflake should be cut in a very large stone. I suggest frosting P10,P4,P3, but others work too. This cuts a little different than normal so watch it, but not hard. For quartz, if the P10 facet is not frosted, change it to 40.75. 15-125 cts.|
At left is the pototype Sonoran Snowflake, a 23.5mm stone cut from rutilated quartz. No facets were frosted on this stone. At right, a beautiful 48mm, 80 carat Sonoran Snowflake from light blue topaz with frosted facets struts its stuff. It was cut by Chris Byron.
This design is for all of the people who like to cut very large, or door knob size stones, 15mm+++. It is fun to cut with not much difficulty. There are a few thing that are a little different to watch for when cutting. The P8's are basically a step cut, and cut in after the P3 and P4 steps are cut.
The P8 facets can be roughed in earlier if you want, to help get the tier sizes right. However all of the tiers on the steps can vary somewhat, the snowflake will look a little different. But then, aren't all snow flakes different? Also unusual is the girdle to crown area, the corners wrap around and meet from the pavilion. These are not hard to cut, but watch the C2 facets, they meet fast. The table is very large and can be hard to polish. It is large so the snowflake shows through it.
There are several ways to frost this pattern, I like it on the P3, P4 and P10 facets. If you are cutting quartz raise the angle on the P10 facets to 40.7, and cut everything else as is. This is very nice and bright in quartz and beryl. Topaz is a little livelier because of the higher RI... The quartz sample is all polished with no frosting and the blue topaz is frosted on the P11, P6, P4, P10 facets.
Enjoy cutting your Sonoran Snowflake! Drop me an email to let me know your results and what you've cut, or feel free to inquire if you have any questions or need some help regarding this design - Jeff.
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