Proportions charts for Emerald & Radiant Cut
| Ideal Cut | Premium Cut | International Fine Trade Cut | US domestic Average Cut | Below Average Cut | ||||
| Cut classes | Class 1A | Class 1B | Class 2A | Class 2B | Class 3A | Class 3B | Class 4A | Class 4B |
| Table, % | 61-63.5 | 63.6-64.1 60.9-60 |
64.2-65.0 59.9-59.0 |
65.1-69.0 58.9-58 |
69.1-74.0 57.9-56.0 |
74.1-76.0 55.9-53.0 |
76.1-78.0 52.9-50.0 |
> 78.0 < 50.0 |
| Crown height, % | 12.3-14.4 | 12.2-11.9 14.5-15 |
11.8-11.5 15.1-15.5 |
11.4-11.1 15.6-16.2 |
11.0-9.5 16.3-17.0 |
9.4-8.5 17.1-18.5 |
8.4-7.8 18.6-19.5 |
< 7.8% > 19.5 |
| Girdle Thikness, % Word description and percentages |
Thin to Medium or Medium to Thick 1% to 3.0% or 1.7% to 5.5% | Thin to Thick 1% to 5.5% > more variance | Very thin to Very thick 0.4% to 7.0% | Extremely thin to Extremely thick 0% to > 7.0% | ||||
| Total Depth, % Determined by factors already considered above |
60-65 | 65.1-69.0 59.9-58.0 |
69.1-74.0 57.9-57.0 |
74.1-78.0 56.9-56.0 |
78.1-80.0 55.9-53.0 |
> 80.0% < 53.0% |
||
| Polish/Symmetry Not a primary determining factor |
Excellent to Good | Good or Fair | Poor | |||||
| Square range Length/Width ratios (Preferences only) |
0.95-1.05 | |||||||
| Rectangular range Length/Width ratios (Preferences only) |
1.5-1.75 | 1.49-1.26 1.76-1.99 |
> Class 3 < Class 3 |
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Jason Withers
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