Glossary · Last updated May 3, 2026
Cut (Diamond)
The GIA grading scale rating how well a diamond's facets reflect light, independent of shape. Grades: Excellent, Very Good, Good, Fair, Poor. Cut affects brilliance (white-light return), fire (color dispersion), and scintillation (sparkle pattern). The most consequential of the 4Cs for photographed sparkle. A well-cut D-color diamond photographs with more fire than a poorly-cut D.
The ten common diamond cuts
Round brilliant — 57-58 facets, the universal sparkle standard, ~75% of engagement-ring market. Princess — square-cornered, modern look, faceted underneath. Oval — elongated brilliant, finger-flattering, trending strongly post-2020. Marquise — pointed elliptical, vintage, looks larger than its carat. Emerald — rectangular step-cut, art-deco, shows clarity prominently. Cushion — square or rectangular with rounded corners, soft romantic. Pear — teardrop, point-up or point-down. Radiant — square emerald-cut hybrid. Asscher — square emerald, distinctive X-pattern in the table. Heart — pointed lobed shape, novelty.
Why each cut photographs differently
Brilliant cuts (round, princess, oval, cushion, radiant, pear, marquise, heart) are designed to maximize light return — they sparkle as moving fire when the stone is rotated. They photograph as bright, with strong specular highlights at the table (top facet). Step cuts (emerald, asscher) prioritize transparency and "hall of mirrors" visual depth over sparkle — they photograph as glassy and reveal inclusions more clearly. Mixing photography style across cut categories breaks visual consistency in a multi-stone listing.
What AI must preserve
Cut shape and facet pattern are the buying decision. A buyer searching for "princess cut engagement ring" who lands on a listing showing an oval stone has been mis-served. AI jewelry retouching preserves the cut's silhouette pixel-faithfully and keeps the signature facet pattern intact (princess's grid of grids; round's kite-and-star pattern; emerald's step-rectangles). Stone color swap (e.g. diamond → sapphire) keeps the cut and only changes the spectrum.
See it in action
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