Purple Cross: Faceting Design Diagram

Tanzanite (Zoisite, Thulite)

Purple Cross (TANZ5.JRG)
By Jeff R. Graham
Copyright 1993
82.7% Light Return
Angles for R.I. = 1.69
69 facets + 12 facets on girdle = 81
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.499 T/L = 0.499
P/W = 0.445 C/W = 0.220
H/W = (P+C)/W+0.02 = 0.685
P/H = 0.650 C/H = 0.321
Vol./W^3 = 0.279

Addition # 3 - This design is good for lighter colored material (it will help darken) and has good flash. It is easy to cut and does not take a lot of time, 1 -6cts(good luck on finding clean Tanzanite in 6cts). This works in Peridot as well as Garnet too... Cut in refractive indexes 1.69 to 2.14 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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