The ags diamond cut grade chart also includes an ideal grade.
Ideal cut grade diamond.
And of all the diamond 4cs it is the most complex and technically difficult to analyze.
Basically even if your diamond has ideal light return it can still receive low proportions grade if the crown angle is too high or the table is too big or some other proportion factor like pavilion angle culet size.
Ags indicates the proportion factors grade if the overall cut grade isn t ags ideal o simply for documentation purposes.
An ideal cut diamond reflects close to 100 of the light that enters through the table and crown facets.
The strictest standards are applied to the round brilliant.
How diamond cut grades are assigned.
Ags diamond quality document ags was the first independent grading organization to utilize a numerical system in their reports with 0 being the highest grade.
Gia diamond cut grading system.
The gia diamond cut grading system assigns one of these five grades to describe the overall cut quality of a standard round brilliant diamond in the gia d to z color range and the flawless to i 3 clarity range.
Cut quality is graded by the ags as ideal excellent very good good fair or poor.
When looking at ags diamonds we recommend only considering ideal cut diamonds for the best quality.
American gem society taking cut grading to a higher level.
As a diamond deviates further from having ideal light performance so does the numerical grading value as it starts increasing from 1 excellent 2 very good.
Conversely a well cut diamond can have a slightly lower color g h or clarity si1 si2 and still look quite beautiful due to its superior ability to create sparkle and.
Excellent very good good fair poor.
Cut grade is the most important factor in determining the overall appearance of a diamond because a poorly cut diamond will seem dull even with excellent clarity and color.
A diamond s cut is evaluated by trained graders with higher grades given to stones whose symmetry and proportions most closely match the particular ideal used as a benchmark.
To determine the cut grade of the standard round brilliant diamond the shape that dominates the majority of diamond jewelry gia calculates the proportions of those facets that influence the diamond s face up appearance.
A diamond s cut is evaluated by trained graders who assess a stone s symmetry and proportions and assign a cut grade based on how closely the diamond matches the particular ideal cut used as a benchmark.
Although its facet count is invariable its proportions are not.
Blue nile offers four different cut grades ideal.
This cut represents roughly the top 15 of diamond cut quality it reflects nearly as much light as the ideal cut but for a lower price.
This rare cut represents roughly the top 3 of diamond cut quality it reflects most of the light that enters the diamond.
To the observer this reflected light is seen fire brilliance and scintillation.
