Inca Dome: 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 "Inca Dome"


Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)

Inca Dome Jeff Graham Facet Design 1Inca Dome Jeff Graham Facet Design 2

Inca Dome (DOME21.JRG)
By Jeff R. Graham
Copyright 2007
85.6% Light Return
Angles for R.I. = 1.62
81 facets + 16 facets on girdle = 97
8-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.277 T/L = 0.277 P/W = 0.405 C/W = 0.319
H/W = (P+C)/W+0.02 = 0.744 P/H = 0.544 C/H = 0.429
Vol./W^3 = 0.247



Addition # 13 - Cut in refractive indexes 1.62 to 2.14 with no changes. This is nice and works well in light to mediumly saturated materials. I like it in mint and fancy colored Garnets as well.

Inca Dome Jeff Graham Facet Design 3

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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