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".


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

Jeff R. Graham

The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as Gram Faceting Designs.

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