| Home | Rough | Bargains | Equipment | Books | Online Designs | Just Ask Jeff | Order | News List | Contact Me | Links |
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Penta Dome (DOME34.JRG)
By Jeff R. Graham
Copyright 2007
82.4% Light Return
Angles for R.I. = 1.62
91 facets + 9 facets on girdle = 100
9-fold, mirror-image symmetry
72 index
L/W = 1.015 T/W = 0.274 T/L = 0.270 P/W = 0.403 C/W = 0.370
H/W = (P+C)/W+0.02 = 0.793 P/H = 0.508 C/H = 0.466
Vol./W^3 = 0.279Addition # 13 - Cut in refractive indexes 1.62 to 2.14 with no changes. This is ideal for lightly saturated materials. It cuts easily and is not difficult. This is very good for pale saturated Afghan Tourmaline.

Random - Cosine - ISO
| Home | Rough | Bargains | Equipment | Books | Online Designs | Just Ask Jeff | Order | News List | Contact Me | Links |