Cut grade (Excellent to Poor)
The grade for how well a standard round brilliant is cut, from Excellent to Poor.
How to read it
GIA’s cut grading system evaluates the cut of a standard round brilliant on a scale from Excellent to Poor; its main parts, from top to bottom, are the crown, girdle and pavilion. The FTC’s jewelry guides set a floor on describing cut: a stone that is lopsided, or so thick or thin as to detract materially from its brilliance, shouldn’t be called properly cut or modern cut.
Also searched as: diamond cut grade, excellent cut, ideal cut.
Grades describe a stone as a grading laboratory saw it. This page explains the grading scales; it doesn’t grade or value any stone.
Read next
- Next in Diamond gradingPrincess cutA square diamond with sharp, pointed corners and a brilliant-style facet pattern.
- The same shape in African flagsFlag of the ComorosThe Comoros flag is four horizontal stripes, yellow, white, red and blue from the top, with a green triangle along the pole holding a white crescent and four white stars in a line between its tips. Norway’s Store norske leksikon explains the crescent as the symbol of Islam and the four stars as the four islands of the Comoros; Lex says the four stripes are said to stand for the islands too.
More diamond grading
The same shape elsewhere
Browse symbols drawn with lines or triangles.
Sources
- Diamond Cut (GIA 4Cs), Gemological Institute of America
- Guides for the Jewelry, Precious Metals, and Pewter Industries (16 CFR Part 23), 16 CFR Part 23 (1 January 2021 edition), Federal Trade Commission, published by the U.S. Government Publishing Office, § 23.16
Researched, edited and approved by Rory Hansen before publishing. Last reviewed September 27, 2026. How we research
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