Topaz (Swiss, Electric, London Blue, Imperial, White, Yellow, Pink, Champange)

Blue Star (TOPAZ3.JRG) 1.69 carats Guerro Topaz
By Jeff R. Graham
Copyright 1993
82.5% Light Return
Angles for R.I. = 1.62
67 facets + 6 facets on girdle = 73
6-fold, mirror-image symmetry
96 index L/W = 1.155 T/W = 0.562 T/L = 0.486
P/W = 0.459 C/W = 0.213
H/W = (P+C)/W+0.02 = 0.692
P/H = 0.663 C/H = 0.308
Vol./W^3 = 0.279

Gram Book 1 – Here is a good design for Topaz with sparkle that is easy to cut. It makes good earrings especially in blue material, 1/2-6cts. Cut in refractive index 1.62 to 2.14 (87.9%) with no changes.


Random – Cosine – ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler