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Seagull Cut: Faceting Design Diagram


Helpful tips, details and guide on Faceting Designs. Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Seagull Cut".

By Jeff R. Graham, updated on

Garnet (Pyrope, Rhodolite, Almandine, Spessartite, Grossular, Demantoid, Tsavorite)

Seagull Cut (GNETP19.JRG)
By Jeff R. Graham
Copyright 1994
78.7% Light Return
Angles for R.I. = 1.73
43 facets + 6 facets on girdle = 49
3-fold, mirror-image symmetry
96 index
L/W = 1.155 T/W = 0.516 T/L = 0.447
P/W = 0.432 C/W = 0.222
H/W = (P+C)/W+0.02 = 0.674
P/H = 0.641 C/H = 0.329
Vol./W^3 = 0.265

Gram Book 1 - This cut is unusual because of the 3/3 split symmetry on the table. It cuts fast and makes a nice 13 ct. stone for earrings or rings. This works in man-made Sapphire and Spinel… Cut in refractive indexes 1.73 to 2.14 (81%) with no changes.


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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