Home Rough Bargains Equipment Books Online Designs Just Ask Jeff Order News List Contact Me Links
Amethyst Aquamarine Beryl Citrine Emerald Garnet Opal Peridot Sapphire Scapolite Spinel Sunstone Topaz Tourmaline Quartz Zircon
Beginner's Page New Stuff Odds & Ends Specials Parcels Synthetics
Cut Gemstones Gemological Information Gemstone Pricing Guides How to buy Gemstones

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

Spokes (MC46.JRG)
By Jeff R. Graham
Copyright 2000
93.2% Light Return
Angles for R.I. = 1.62
49 facets + 12 facets on girdle = 61
6-fold, mirror-image symmetry
96 index
L/W = 1.059 T/W = 0.327 T/L = 0.308
P/W = 0.447 C/W = 0.179
H/W = (P+C)/W+0.02 = 0.646
P/H = 0.692 C/H = 0.277
Vol./W^3 = 0.220

Addition # 7 - I designed this for medium saturated material and use it for earrings. The spokes show up on the crown nicely. This works well in Garnet and Sapphire with no changes.

 

 


Random - Cosine - ISO

Return to OnLine Design Index

Home Rough Bargains Equipment Books Online Designs Just Ask Jeff Order News List Contact Me Links


Copyright 1998-2007 Gram Faceting - All Rights Reserved.