Diamond cutting & polishing is the art, skill and science of transforming a rough stone into a brilliant diamond.
'Cut' has two meanings in relation to diamonds. The first is the shape: round, oval and so on. The second relates to the specific quality of cut within the shape and the quality and price will vary very greatly based on the cut quality. Read more about at Wikipedia, the art of diamond cutting
Shape is the model or form of the diamond, such as round, oval, pear, princess and more.
Cut refers to proportions and the finish grade.
The cut is the most important element to reflect brilliance and is determinable by 3 separate descriptions:
The sparkling quality of the cut is to be determined by 3 separate factors:
What are ideal cut diamonds?
if yo do not want to get crazy to find out the best cut by yourself...
If you are not a professional or familiar with the cut grading,
trust the independent, best Gemological Laboratory:
GIA, HRD or IGI
View the diamond loose and its genuine grading document
at the diamantaire.
The trustworthy grading and Diamond Certificates are mostly from:
HRD – Diamond High Council of Antwerp World Diamond Center (non profit!)
GIA – Gemological Institute of America
How Diamond Laboratories grade Cut: Proportions - Polish - Symmetry
Too shallow and / or too deep cut diamonds will loose brilliance through the side and bottom.
The result is a dull diamond with less brilliance, affecting the ultimate value in terms of quality and price!
Excellent, Very Good, Good, Fair, Poor or Unusual
Finish grade or polish for ideal cut diamonds are described as following:
All facets of a diamond are carefully polished to eliminate all imperfections, characteristics such as abrasions,
scratches, nicks and polishing marks on the surface of the diamond to give the mirror shine and the final beauty touch.
Polish grading: Excellent, Very Good, Good, Fair, Poor or Unusual
is the balance and regularity / evenness of facets.
Facets are compared in opposing pairs, defined as following:
Symmetry grading: Excellent, Very Good, Good, Fair, Poor or Unusual
Triple Excellent cut
When proportions, Polish and Symmetry are graded Excellent it is named Triple Excellent
Ideal cut = Perfect cut = Triple Excellent + Hearts & Arrows = Best Value!
When Proportions, Polish, Symmetry are graded Excellent
Measurements for Round Brilliant diamonds Measurements of fancy cut diamonds
I repeat once again:
if you do not want to get crazy to find out the best cut by yourself's... If you are not a professional or familiar with the cut grading, trust
the independent Grading by a reputable GIA, HRD or IGI Gemmological Laboratory. Best view the diamond loose and its genuine grading document
at the diamantaire.
If you are not sure, trust the opinion of the Expert, the independent Grading by a reputable Gemmological Laboratory!
Proportions: Total depth % Table % Crown % Crown angle ° Pavilion % Pavilion angle °
Excellent: 58.0 - 63.5 52.0 - 63.0 12.0 - 16.5 31.5 - 36.5 42.0 - 44.5 40.0° - 41.7°
Very Good: 55.0 - 65.5 52.0 - 66.0 10.0 - 17.5 28.5 - 38.0 41.5 - 45.0 39.7° - 42.3°
Good: 53.0 - 69.0 50.0 - 70.0 8.5 - 19.0 26.0 - 40.0 41.0 - 46.5 39.4° - 42.9°
Fair & poor: less than less than less than less than less than less than
Thin to slightly thick is OK