Diamond proportions work as a system. A table or depth percentage can orient a comparison, but the combined geometry, finish, weight distribution, face-up appearance, and applicable grading method determine what that number means for a specific stone.
A beyond-the-number guide that places table, depth, crown, pavilion, girdle, culet, symmetry, polish, weight distribution, and face-up light pattern into one connected proportion review.
What this guide covers
- Confirm shape, cutting style, laboratory, and report scope.
- Read measured fields as an interacting proportion set rather than pass-fail numbers.
- Connect the record to face-up appearance, motion, spread, and setting context.
Move beyond isolated percentages
Upper geometry
Read table, crown height, and crown angle together where those fields are available and methodologically comparable.
Lower geometry
Consider total depth, pavilion depth or angle, culet, and how their interaction affects the light path.
Perimeter and weight
Review girdle description, diameter or dimensions, and weight ratio for spread and durability tradeoffs without assuming wider is always better.
Finish and face-up view
Keep symmetry, polish, brightness, fire, scintillation, and dark-light pattern beside the measurements.
Compare proportion sets in sequence
- 1 — Normalize the method
Compare the same shape and compatible report definitions before placing percentages side by side.
- 2 — Look for interactions
Ask how crown, pavilion, table, depth, girdle, culet, symmetry, and polish combine rather than optimizing each alone.
- 3 — Test the visual result
View each stone under consistent lighting and movement, then record preference without rewriting it as a grade.
No single number can grade the stone
Scope boundary · evidence version 2026-07-19
This page does not publish universal ideal ranges, calculate cut grade, compare incompatible report methods, or predict light performance from a proportion field. Shape, eligibility, the complete measured set, finish, condition, and direct observation remain necessary.
Diamond proportion questions
Is there one ideal table percentage?
No. Table interacts with crown, pavilion, depth, girdle, culet, finish, and the applicable cut system.
Does a shallower stone always look larger?
Not as a universal rule. Review actual millimeter dimensions, outline, weight distribution, light pattern, and durability tradeoffs.
Can proportions replace viewing the diamond?
No. They provide evidence about geometry, while direct observation reveals the particular face-up experience.