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“88” Around: Faceting Design Diagram


Details and guide for Faceting Design Diagrams. This design is an "88 Around". Its a nice change from a regular "RB". Great in pink Tourmaline from Nigeria.

By Jeff R. Graham, updated on

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

"88" Around (MC17.JRG)
By Jeff R. Graham
Copyright 1999
83% Light Return
Angles for R.I. = 1.62
61 facets + 8 facets on girdle = 69
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.531 T/L = 0.531
P/W = 0.445 C/W = 0.182
H/W = (P+C)/W+0.02 = 0.648
P/H = 0.688 C/H = 0.281
Vol./W^3 = 0.228

Addition # 4 - This one is a nice change from a regular "RB". I use it in light to medium material, it is great in pink Tourmaline from Nigeria. It is pretty easy, 2cts+. Works in Topaz and Peridot also… Cut this in R.I. 1.62 to 2.14 (92.1%) without changes.


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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