Faceting Design Diagram: P-Eight – Peridot – Olivine, Green, apple green to yellow green


Peridot (Olivine, Green, apple green to yellow green)

P-Eight (PDOT5.JRG)
By Jeff R. Graham
Copyright 1994
87.1% Light Return
Angles for R.I. = 1.67
57 facets + 8 facets on girdle = 65
8-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.487 T/L = 0.487
P/W = 0.397 C/W = 0.161
H/W = (P+C)/W+0.02 = 0.578
P/H = 0.687 C/H = 0.279
Vol./W^3 = 0.186

Addition # 2 – For when you feel like cutting a round but do not want to cut a standard round brilliant . This design makes a nice change of pace and has a nice light return. Light to medium material, 1-6cts. Cut in refractive indexes 1.67 to 2.14 (87.9%) with no 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.