|The 'Freeborn' John (Lilburne) by Carl R. Downey, firstname.lastname@example.org 5-2-96|
|Named for a guy that influenced our Founding Fathers|
|Angles for R.I. = 1.62 (Topaz)||61 facets + 6 facets on girdle = 67|
|2-fold, mirror-image symmetry||96 index|
|L/W = 1.466 T/W = 1.014 T/L = 0.692||P/W = 0.681 C/W = 0.128|
|H/W = (P+C)/W+0.02 = 0.829||P/H = 0.821 C/H = 0.154|
|Vol./W^3 = 0.421|
|cut to temporary culet|
|2||90.00||24-72||Cut to meet edge from culet as shown|
|3||90.00||06-42-54-90||Meet 1 & 2 to complete outline|
|4||72.29||24-72||Meet at corners - CAREFULLY!|
|5||72.29||06-42-54-90||Meet 1,2,3,4 at corners|
|The step 5 facets will require a lot of time polishing|
|On small stones try 41.7 for ALL pavilion mains|
|a||38.00||06-42-54-90||Meet corners, establish girdle|
|b||28.26||03-45-51-93||Meet a-a, 3-3|
|d||28.26||23-25-71-73||Carefully meet a-c-2-3 (polish last)|
|T||00.00||Table||Cut to a-b-c|
|On small stones try deleting 'd' and cut 'e' @ 28.26|
Well, I wish I could say that the idea for the 'Freeborn ' John (Lilburne) cut was inspired by a shape that I saw somewhere, something I had read or a 'vision'. It was born out of a mind full of frustrated rage! I owned a small 'champagne' colored topaz whose shape seemed to require a marquis. But I hate marquis cuts! The gauntlet was down! No mere mineral was going to get the best of this animal!
So, I looked at some ovals, but I had just finished a Barion oval (highly recommended) and wanted to do something different. Well, Mr. Strickland's GemCad was no longer a mystery to me (although I still have not yet trained myself on ALL the shortcuts/features) having entered, corrected, altered and 'angle translated' printed cuts from 3-4 sources.
Feeling somewhat lazy I thought of a shape with as few sides as possible but WITHOUT marquis-type 'pointy' ends. An 'oblong hex' (elongated or stretched might be a better term - now I think of it!) came to mind. The best place to start most designs is the most critical feature: the pavilion. Sometimes, designing gemcuts is done 'backwards and sideways' compared to the final cutting sequence.
Mentally overlaying an oblong hex on a series of 'break facets' indicated the 'corners' as useful meetpoints. This would make it a little easier to use the stone as a guide during cutting instead of trying to take measurements. Next was 'marrying' the outline to the pavilion. BARION type facets did the trick. (later, while trying to polish a stone with - effectively - FIVE TABLES, I'd realize a convenient construction element would mean slow cutting!). A simple 'cardinal cut' table looks a little better than step cuts but I have used both.
Also, the pavilion mains could be deleted but I prefer them. This general technique/cut can be used with other indexes. (I've designed one for the 80). The tiny barion-type facets on the ends could easily be deleted. Since I'm writing this primarily for other GemCad users, by running this cut through GemRay you will find appropriate positions for 4 symmetrically located jewelry prongs at some 'dark spots' about 1/3 in from the ends! I wish I could say I designed it that way! ;-)
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