Fig.2 shows the Princess crown with beveled corners. This is pretty straightforward. The only data listed by AGS to find the cut-grade in their charts are the slopes of the two main facets, C1 and C2, and table size. These do not completely define the crown.
AGS assumes that the azimuth of the 'star' facets is 6º*; this defines the table. They also assume that main facets C1 & C2 are of equal width at the mid-side. With these assumptions the crown is completely defined; the height, and the slopes of the corner and star facets can be determined from these data.
If a cutter uses different assumptions the crown will have a different height and the slopes of the corner and star facets will be different. This will produce a real image which is different from that generated by the computer-model and may not comply with the AGS grade.
 |  |
Fig.1 The shape of the Princess retains much
weight of a well-formed octahedral crystal. | Fig.2 The crown initially cited by AGS. |
* GemCAD data listed by AGS in one publication cite the index as 1/64 circle, = azimuth of 5.625º but the other data in the same chart agree with 6º azimuth (= index of 1/60 circle).