Line Point Triangle: Faceting Design Diagram

Helpful tips and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Line Point Triangle"


Spinel (Red, Pink, Lavender, Green, Blue, Orange, Violet)

Line Point Triangle (SPINEL1.JRG)
By Jeff R. Graham
Copyright 1995
87.2% Light Return
Angles for R.I. = 1.71
31 facets + 12 facets on girdle = 43
3-fold, mirror-image symmetry
96 index
L/W = 1.104 T/W = 0.496 T/L = 0.449
P/W = 0.481 C/W = 0.188
H/W = (P+C)/W+0.02 = 0.689
P/H = 0.698 C/H = 0.273
Vol./W^3 = 0.211

Addition # 2 - This triangle cuts easily and makes a nice stone in about any type of material, 1/2-4cts. I like it in light colored Garnet and Sapphire. Cut in refractive indexes 1.71 to 2.14 with no changes. This design is deceptive, it is really quite nice.

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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