P-Eight: Faceting Design Diagram

Successful tips, details, and guide on Faceting Designs. Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "P- Eight"


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

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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