Faceting Design Diagram: Diamond Eye 1.50 – Tourmaline – Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite


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

Diamond Eye 1.50 (CHECK82.JRG)

By Jeff R. Graham

Copyright 2003

76.5% Light Return

Angles for R.I. = 1.62

35 facets + 12 facets on girdle = 47

2-fold, mirror-image symmetry

96 index

L/W = 1.502

T/W = 0.421

T/L = 0.280 P/W = 0.430 C/W = 0.232

H/W = (P+C)/W+0.02 = 0.682

P/H = 0.631

C/H = 0.340

Vol./W^3 = 0.264

 

Addition # 8 – This is brighter than the ray trace may lead you to think and works well in about any material. There are not very many 1.50 marquises around that are worth cutting and it cuts fast and is nice. It is very pretty in pink Tourmaline.

Random – Cosine – ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

Gram Faceting Archive of Information
This edited version of an article by the late Jeff Graham is part of a special archived informational series from Gram Faceting. Used with permission.