< Back About Tiffany Engagement Rings

beyond the 4Cs

The superlative beauty of Tiffany engagement diamonds
can be explained by the strict quality standards
that go well beyond the popular but oversimplified 4Cs.


Cut—the precise shape and positioning of a diamond’s facets—is the most important factor in determining the stone’s beauty. Many diamond cutters choose to place the size of the diamond above its potential beauty, sacrificing the ideal balance of brilliance, dispersion and scintillation. Tiffany diamond cutters refuse to make this compromise; when the choice is size or beauty, we always choose beauty.

Melvyn Kirtley, Tiffany's chief gemologist, discusses the importance of a diamond’s cut.

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Clarity measures the flawlessness of a diamond and correlates directly to its value. A stone is said to be flawless if, under 10-power magnification, no internal flaws (clouds, feathers, pinpoints) or external imperfections (scratches, pits, nicks) are visible. Absolutely flawless diamonds are exceedingly rare.

Gem-grade diamonds are given a clarity rating based on a scale that is standard in the trade. However, when Tiffany believes that a diamond’s clarity is on the borderline between two grades, Tiffany will always give the stone the lower grade.

view diamond clarity scale

Learn more about Tiffany diamond color evaluation.

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The ideal engagement diamond is clear to the point of being colorless. At Tiffany, laboratory experts determine the color of each diamond by comparing it to authenticated “master” diamonds. Each stone is then color-graded to a precise scale from “D” (colorless) to “Z” (saturated). Only diamonds of “I” level (near colorless) or better are accepted at Tiffany.

view diamond color scale

carat weight

“Carat” denotes the weight of a diamond. One carat equals 0.20 grams. Tiffany measures diamonds to 1/1000th of a carat. Taken by itself, carat weight does not determine a diamond’s value. For example, two one-carat stones can vary widely in price when clarity, color, cut and presence are taken into consideration.

Tiffany diamonds are cut to maximize brilliance. Others are cut to maximize carat weight. The difference is legendary.

The Tiffany Gemological Laboratory

Tiffany & Co. maintains a state-of-the-art diamond grading facility with a staff of highly experienced gemologists.

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Tiffany frequently rejects stones that would be accepted by others.


Tiffany & Co. has additional diamond quality standards that go beyond the 4Cs. Precision of cut reflects a diamond cutter’s mastery of his craft and his ability to create the correct facets of a beautifully scintillating Tiffany diamond. Symmetry refers to perfectly proportioned cuts that rule out the appearance of off-center tables and culets, misshapen facets and wavy or non-parallel girdles and tables. A diamond’s high polish rating helps ensure that a diamond’s beauty is accentuated and not compromised. In Tiffany’s relentless pursuit of diamond beauty, we insist upon superior polish, symmetry and precision of cut.