The ideal star facet is an equilateral triangle.

The ideal star facet shape is an equilateral triangle, (all three sides equal in length). The star facet should reach a touch less than half-way down the crown. Unfortunately not all stars are cut to these parameters. If the stars are long, this will cause the false estimate of a smaller table, using the Table Percentage Bowing Method. If the stars are short, an outward bow would occur, giving the impression of a larger than actual size. If this is the case with long, short, or inconsistent stars, adjustments must be made to compensate for that, in an estimate. Another course of action would be to use an alternate method for calculating table size.