Open13.019 Cushion Triangle
Steele, Norman W; Seattle F Design, Oct 1974; L/W=1.016 H/W=0.706 Vol/W³=0.236 96 index 43+12 facets

13.020 Trillium
Cornwall, John R; Rock & Gem, Mar 1979, p20; L/W=1.018 H/W=0.571 Vol/W³=0.215 96 index 46+12 facets

13.021 Trefoil
Naples, Donald G; Lapidary Journal, Sep 1979, p1278; L/W=1.019 H/W=0.685 Vol/W³=0.241 72 index 73+0 facets

Open13.022 London Shield
(Durham) Steele, Norman W; Seattle F Design, Oct 1988, p3; L/W=1.010 H/W=0.663 Vol/W³=0.226 96 index 52+9 facets

13.022A London Shield Variation
Ricks, Tom; Facets, Mar 1980, p4; L/W=1.009 H/W=0.659 Vol/W³=0.221 96 index 52+9 facets

13.022B London Shield Alternate
Ricks, Tom; Facets, Mar 1980, p4; L/W=1.009 H/W=0.746 Vol/W³=0.228 96 index 51+9 facets

13.023 Trilliond
Gerding, A L; Facets, Nov 1980, p3; L/W=1.113 H/W=0.775 Vol/W³=0.229 96 index 43+12 facets

13.024 Minuet Variation
Carlson, Robert L; Facets, Sep 1980, p3; L/W=1.113 H/W=0.653 Vol/W³=0.186 96 index 43+6 facets

Open13.025 Curved Triangular Brilliant
Carroll, J W; Angles, May 1981; L/W=1.005 H/W=0.614 Vol/W³=0.191 96 index 46+12 facets

13.026 FVS-26 Tri-Curve Barion 2 Main
Van Sant, Fred W; Star Cuts I (1980) p26; L/W=1.054 H/W=0.530 Vol/W³=0.197 96 index 61+18 facets Pavilion Only

Open13.026A FVS-26 Tri-Curve Barion, 2-Main
Van Sant, Fred; Star Cuts I (1988); L/W=1.000 H/W=0.549 Vol/W³=0.175 72 index 79+18 facets

13.027 FVS-25 Tri-Curve Barion 3-Main
Van Sant, Fred W; Star Cuts I (1980) p25; L/W=1.001 H/W=1.155 Vol/W³=0.637 96 index 82+24 facets

Open13.027A FVS-25 Tri-Curve Barion, 3-Main
Van Sant, Fred; Star Cuts I (1988); L/W=1.000 H/W=0.549 Vol/W³=0.175 96 index 85+24 facets

13.028 Four Main Tri-Curve Barion
Van Sant, Fred W; Star Cuts I (1980) p26; L/W=1.027 H/W=0.591 Vol/W³=0.195 96 index 103+24 facets

13.029 FVS-27 Tri-Curve Spike 72
Van Sant, Fred W; Star Cuts I (1980) p27; L/W=1.029 H/W=0.559 Vol/W³=0.173 72 index 61+18 facets

Open13.029A FVS-27 Tri-Curve Spike
Van Sant, Fred; Star Cuts I (1988); L/W=1.000 H/W=0.564 Vol/W³=0.177 72 index 64+18 facets

13.030 Trigon #2
Ricks, Tom; Stonecutter, Nov 1981, p3; L/W=1.024 H/W=0.727 Vol/W³=0.254 96 index 85+12 facets

Open13.031 Trion /c/
(Van Sant) Steele, Norman W; Seattle F Design, Mar 1982, p4; L/W=1.015 H/W=0.532 Vol/W³=0.171 72 index 57+9 facets

Open13.031A FVS-53 Trion
Van Sant, Fred; Star Cuts I (1988); L/W=1.015 H/W=0.565 Vol/W³=0.180 72 index 58+9 facets

Open13.032 Trilliant B
Watermeyer, Basil; Diamond Cutting v1 (1980) p35; L/W=1.037 H/W=0.703 Vol/W³=0.261 96 index 40+12 facets