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Classic I gem designClassic I gem design

Classic I: Faceting Design Diagram


Detailed information and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Classic I".

By Jeff R. Graham, updated on

Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)

Classic I gem design

Classic I (MC26.JRG)
By Jeff R. Graham
Copyright 1999
88.6% Light Return
Angles for R.I. = 1.62
49 facets + 12 facets on girdle = 61
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.558 T/L = 0.558
P/W = 0.442 C/W = 0.164
H/W = (P+C)/W+0.02 = 0.626
P/H = 0.706 C/H = 0.262
Vol./W^3 = 0.252

Addition # 4 - This is one of my favorites to cut, it is fast and easy. Also this is such a classic shape most jewelers love to use it, and more important buy it. It works in any decent rough, 1cts+. Cut this in R.I. 1.62 to 2.14 (87%) without changes.


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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