Faceting Design Diagram: Red Block – Garnet – Pyrope, Rhodolite, Almandine, Spessartite, Grossular, Demantoid, Tsavorite


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

Red Block (MC15.JRG)
By Jeff R. Graham
Copyright 1999
87.6% Light Return
Angles for R.I. = 1.73
35 facets + 8 facets on girdle = 43
2-fold, mirror-image symmetry
96 index
L/W = 1.330 T/W = 1.047 T/L = 0.787
P/W = 0.464 C/W = 0.127
H/W = (P+C)/W+0.02 = 0.611
P/H = 0.759 C/H = 0.208
Vol./W^3 = 0.442

Addition # 4 – This can be cut in several different cutting orders, and is not an easy design (because of the keel). I think doing a 1.33 L/W preform is a good start. The P6 can be deeper or shallower depending on the rough, the C2 would have to change, light to medium material 2cts+. This is designed for yield, which is why the Pavilion is so deep, it will darken the finished stone. Cut this in R.I. 1.73 to 2.14 without changes.

 


Random – Cosine – ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

Gram Faceting Archive of Information
This edited version of an article by the late Jeff Graham is part of a special archived informational series from Gram Faceting. Used with permission.