| 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 |
Sapphire / Corundum (Ruby, Ceylon, Padparadschah, Pink, Yellow, Green)
Three Blade Triangle (SAP1.JRG)
By Jeff R. Graham
Copyright 1994
82.5% Light Return
Angles for R.I. = 1.76
88 facets + 15 facets on girdle = 103
3-fold, mirror-image symmetry
96 index
L/W = 1.028 T/W = 0.507 T/L = 0.494
P/W = 0.398 C/W = 0.193
H/W = (P+C)/W+0.02 = 0.611
P/H = 0.652 C/H = 0.315
Vol./W^3 = 0.199Gram Book 1 - This triangle has a lot of facets and should be cut in a medium to large size stone. This is really designed for man-made materials. It is a harder design to cut than some, pay attention to the meets. Any color material in light to medium color, 2-16cts. Cut in refractive index 1.78 to 2.14 (82%) with no changes.

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