Faceting Design Diagram: Line Point Triangle – Spinel – Red, Pink, Lavender, Green, Blue, Orange, Violet


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

About the author
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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