Delta “T”: 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 "Delta "T" ".


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

Delta "T" (PDOT8.JRG)
By Jeff R. Graham
Copyright 1998
76% Light Return
Angles for R.I. = 1.67
34 facets + 9 facets on girdle = 43
3-fold, mirror-image symmetry
96 index
L/W = 1.053 T/W = 0.611 T/L = 0.580
P/W = 0.487 C/W = 0.223
H/W = (P+C)/W+0.02 = 0.730
P/H = 0.668 C/H = 0.305
Vol./W^3 = 0.249

Addition # 3 - The P3 cuts to center point, when they look like long straight sided rectangles(3) they are right. You may have to fish a little. The rest of this design cuts easy, any material, 1-8cts. Cut in refractive indexes 1.67 to 2.14 (78.6%)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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