Faceting Design Diagram: Edge Oval – Spinel – Red, Pink, Lavender, Green, Blue, Orange, Violet

Spinel (Red, Pink, Lavender, Green, Blue, Orange, Violet)

Edge Oval (SPINEL6.JRG)
By Jeff R. Garaham
Copyright 1998
83% Light Return
Angles for R.I. = 1.72
67 facets + 12 facets on girdle = 79
2-fold, mirror-image symmetry
96 index
L/W = 1.330 T/W = 0.639 T/L = 0.481
P/W = 0.457 C/W = 0.175
H/W = (P+C)/W+0.02 = 0.652
P/H = 0.701 C/H = 0.268
Vol./W^3 = 0.295

Addition # 3 – Cut a preform for 1.33 L/W, this is important because the P1,P3,P5 are just barely NOT cut to center point. You cut to point in P10,P11. This is not really hard to cut and is great in spinel, 1-18cts. This works in Garnets, YAG, and Sapphire.

Random – Cosine – ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

About the author
Jeff R. Graham
The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as Gram Faceting Designs.
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