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BP Star: Faceting Design Diagram


Detailed information and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "BP Star".

By Jeff R. Graham, updated on

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

BP Star (PDOT6.JRG)
By Jeff R. Graham
Copyright 1995
83.6% Light Return
Angles for R.I. = 1.67
56 facets + 10 facets on girdle = 66
5-fold, mirror-image symmetry
80 index
L/W = 1.051 T/W = 0.570 T/L = 0.542
P/W = 0.449 C/W = 0.190
H/W = (P+C)/W+0.02 = 0.659
P/H = 0.681 C/H = 0.289
Vol./W^3 = 0.248

Addition # 3 - The C3 facets can be cut before the C2's if you want to, otherwise this design cuts normally and you should not have any problems. It makes a very nice stone in any material, 1-8cts. Cut in refractive indexes 1.67 to 2.14 with no changes.


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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