Faceting Design Diagram: 8-Swirl – Garnet – Pyrope, Rhodolite, Almandine, Spessartite, Grossular, Demantoid, Tsavorite


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

8-Swirl (GNETA1.JRG)
By Jeff R. Graham
Copyright 1993
90.9% Light Return
Angles for R.I. = 1.78
57 facets + 8 facets on girdle = 65
8-fold symmetry
96 index
L/W = 1.000 T/W = 0.403 T/L = 0.403
P/W = 0.375 C/W = 0.141
H/W = (P+C)/W+0.02 = 0.536
P/H = 0.699 C/H = 0.263
Vol./W^3 = 0.198

Gram Book 1 – A nice design for colored Garnet (notice the 1.78 R.I). It is a little different to cut. The facets cut fast, watch out. I prefer this design in a light Garnet like a Mali. Cut in refractive index 1.78 to 2.14 (92.6%) with no changes.


Random – Cosine – ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler