Sunstone (Feldspar, Bytonite, Labradorite, Spectrolite, Orthoclase)
Shovel Head (SUN1.JRG)
By Jeff R. Graham
Copyright 2006
85.9% Light Return
Angles for R.I. = 1.54
41 facets + 8 facets on girdle = 49
8-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.530 T/L = 0.530 P/W = 0.466
C/W = 0.204 H/W = (P+C)/W+0.02 = 0.690 P/H = 0.676 C/H = 0.295 Vol./W^3 = 0.286
PAVILION
CROWN
Addition # 11 – This is a deep cut to help give life to dull colored Sunstone. Cut in refractive indexes 1.54 to 2.14 with no changes. The pavilion is designed not to mix color and this works well for watermelon bulls eye material. Note: You can cut the girdle and the pavilion at the P3 angle to meet then cut them down at P1. C2 can vary depending on saturation and stone depth.
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
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