Sunstone (Feldspar, Bytonite, Labradorite, Spectrolite, Orthoclase)
Repose (SUN20.JRG)
By Jeff R. Graham
Copyright 2006
87.4% Light Return
Angles for R.I. = 1.54
73 facets + 8 facets on girdle = 81
8-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.609 T/L = 0.609 P/W = 0.557
C/W = 0.141 H/W = (P+C)/W+0.02 = 0.718 P/H = 0.775 C/H = 0.197 Vol./W^3 = 0.296
PAVILION
CROWN
Addition # 11 – Cut in refractive indexes 1.54 to 2.14 with no changes. This is excellent in about any colored material and works well in Beryl. It cuts fairly easy and fast I prefer lightly saturated materials. Note: The girdle can be cut in first and the P1 cut to meet so that center point is not needed and it saves rough.
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
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