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What is Difference Between Excellent vs Ideal Cut Diamond ?
What is the difference between Excellent and Ideal Cut? When it comes to diamonds, cut is one of the most essential criteria in defining their beauty and quality. The cut refers to a diamond's angles and proportions, which affect its ability to reflect and refract light. This produces the diamond's brightness, fire, and scintillation. While all well-cut diamonds shine, their cut grade varies. Here, we'll discuss the key distinctions between the top two cut grades.
Quick Facts
The Gemological Institute of America (GIA) grades diamonds in five categories based on their cut: ideal, excellent, very good, good, or fair. To attain an ideal or excellent cut grade, diamonds must meet exacting criteria for symmetry, polish, and critical angles. These two categories represent the best cut quality and lighting performance.
An ideal cut is the highest cut grade a diamond can receive. It exhibits a perfect combination of angles and facets that allow nearly all light to reflect internally and refract back through the top of the stone. This creates the ultimate sparkle and fire with no observable weaknesses. As you may imagine, ideal-cut diamonds are rare and carry hefty price tags.
Excellent cuts come close to the light return of ideal cuts but have minor variances in symmetry or angles that keep them from reaching that pinnacle category. To the untrained eye, they appear identical in brilliance and beauty. However, excellent cuts represent better value since their price is discounted compared to ideal cuts of similar size and quality.
Diamond Cut
A diamond's cut relates to the finished stone's angles, dimensions, symmetry, and polish. It is influenced by characteristics such as table percentage, depth %, crown angle, and pavilion angle. The way a diamond is cut has a direct impact on its appearance and performance.
Proper cutting is what unlocks a diamond’s inherent brilliance and fire. When light enters the diamond, it gets refracted off the pavilion facets and reflected off the crown facets. As the light travels outward, it splits into the colors of the rainbow. This scattered light is what gives diamonds their sparkle and flashes of color. The degree of brilliance and fire depends largely on how expertly the diamond is cut.
Well-cut diamonds have an ideal balance of depth and width to promote light return and minimize leakage. The facets are symmetrical and aligned at optimal angles to achieve the best interaction with light rays. Precise cutting is what allows diamonds to reflect and refract light most effectively. It takes master precision and calculated decision-making by diamond cutters to maximize a diamond’s optical properties. Even slight deviations from ideal proportions can impact fire, brilliance, and scintillation. The cut is truly the most complex and technically demanding of the 4Cs.
What Determines Cut Grade?
A diamond’s cut grade is an assessment of its finish, design, and facet arrangement. Multiple factors are considered when determining where a diamond falls on the GIA’s cut scale.
The first criteria are polish and symmetry. Well-cut diamonds have smooth, mirrored facets and symmetrical designs. Next, proportions like table percentage, depth percentage, crown angle, and pavilion angle are measured. These numbers can’t deviate far from the ideal ranges, or light performance will suffer.
Precision is also assessed by analyzing lower girdle facets, star facets, bezel facets, and other facet arrangements. The girdle thickness and culet size are inspected as well. Then, light behavior is considered. Diamonds with ideal proportions will exhibit a balanced fire and brilliance without leakage or dull areas.
By compiling this data, GIA gemologists can grade the cut. The top tier is Ideal – indicating a perfect combination of angles/facets for maximized brilliance and fire. The second level is Excellent, meaning the diamond still shows exceptional light performance with minor variances. Very Good and Good represent quality cuts with noticeable, but not excessive, light leakage. The lowest grade is Fair, given to diamonds with poor cut quality and light return.
This comprehensive grading system allows the subtle differences between an ideal and excellent cut to be quantified and communicated. But to the naked eye, both still look exquisite.
Ideal Cut
An ideal cut diamond represents the pinnacle of cutting standards. It has perfect polish, symmetry, and aligned facets with proportions that fall within the ideal ranges for maximizing brilliance and fire. Ideal cuts reflect and refract nearly all light that enters the diamond rather than allowing light to leak out the sides or bottom. This results in the most intense sparkle and light return.
To achieve this top-tier cut grade, diamond cutters meticulously plan the table size, crown height, pavilion depth, and other angles. Each facet is precisely placed to optimize the internal reflection and refraction of light. The craftsmanship requires immense expertise and care. Even minuscule deviations can result in lost light performance.
Less than 3% of diamonds are graded as Ideal cuts since the standards are so rigorous and demanding. These diamonds clearly stand above the rest in terms of cut quality and beauty. As a result, ideal cuts command significantly higher prices compared to very good or good cuts of similar carat weights, colors, and clarities. For diamond connoisseurs, the premium pricing reflects the breathtaking optical properties of a flawlessly cut diamond. But excellent cuts offer comparable beauty at more accessible price points.
Excellent Cut
Diamonds graded as Excellent cuts represent the second highest tier of GIA’s cut scale, just below Ideal. They exhibit a near-perfect combination of factors like table and depth percentages, crown angle, pavilion angle, girdle thickness, symmetry, and polish. Though Excellent cuts have minor variations from the optimal proportions, the differences are negligible to the naked eye.
Excellent cuts reflect and refract the vast majority of the light that enters, creating outstanding brilliance and fire. The light return is just slightly less than an Ideal cut diamond, but the average person would be hard-pressed to see a difference. Excellent cuts still showcase a mesmerizing balance of brightness and color flashes.
Achieving an Excellent cut grade still requires immense skill on the part of diamond cutters. The angles and alignments are very precise, though they may not reach mathematical perfection like an Ideal cut. Since Excellent cuts represent the second tier, not the top, they are discounted in price compared to Ideal cuts of similar carat weights, colors, and clarities. For shoppers wanting superb light performance without the higher cost, Excellent cuts offer tremendous value and beauty.
Comparison of Excellent vs. Ideal Cuts
When directly comparing Ideal and Excellent cuts, there are small but measurable differences in light performance. Ideal cuts represent absolute optical perfection, maximizing light return to create unrivaled brilliance and fire. Excellent cuts reflect and refract just a bit less light due to minute variations in symmetry, table size, crown angles, or other proportions. These tiny deviations from the ideal do subtly impact the spread of light within the diamond.
However, only a trained gemologist using specialized tools would likely notice these subtle performance gaps. To the naked eye, an Excellent cut appears just as dazzling as an Ideal cut. The difference is not visible under normal viewing conditions. Yet, there is a significant price premium for that barely detectable edge in optical perfection.
Ideal cuts fetch higher prices for their flawless light behavior. But Excellent cuts cost considerably less while offering beauty that’s realistically indistinguishable from an Ideal. For shoppers who prioritize value, Excellent cuts provide enormous savings over Ideal cuts of comparable size, color, and clarity. You still get exquisite brilliance and fire without overpaying purely for that Ideal label. For most buyers, the smart choice is an Excellent cut.
Diamond Cut is Not the Same as Diamond Shape
When shopping for a diamond, it’s important to understand that a diamond’s shape and a diamond’s cut grade are two distinct attributes. While shape refers to the diamond’s geometric form, cut refers to the quality of its proportions and facet arrangement. Both factors influence a diamond’s visual appeal but serve different purposes.
What is a Diamond Shape?
Diamond shapes include classic rounds, princess, cushion, oval, radiant, pear, marquise, emerald, and Asscher cuts. Shape impacts the outline of the diamond, aesthetic appeal, and face-up appearance. Certain shapes like cushion and oval diamonds have an antique charm, while modern brides may prefer a round brilliant or princess cut.
However, note that in conversation and in some written accounts, shapes are referred to as cuts. Round brilliant cut diamonds and princess cut diamonds are common examples of this pattern.
On the other hand, a diamond’s cut grade evaluates the skill, technique, and mathematical precision that went into cutting and polishing the raw stone. Cut grades include ideal, excellent, very good, good, fair, and poor.
Cut grades analyze factors like table size, crown angle, pavilion depth, girdle thickness, culet size, polish, and symmetry. A well-cut diamond follows strict proportional guidelines to allow light to refract optimally off a diamond’s facets. The difference between excellent and ideal cuts is that ideal represents the strictest parameters to achieve maximum light return.
When choosing a diamond, selecting a shape you love is just as important as prioritizing cut quality. A cushion cut with an ideal cut grade will not necessarily look better than a princess cut with an excellent cut. The right balance depends on your preferences. However, sticking with excellent or ideal cut diamonds ensures you get a stone with superb optical performance.
Understanding how cut brings out a diamond’s hidden beauty while shape creates the outline empowers diamond buyers to get the best of both worlds. Seek a shape that resonates with you, then examine cut grades to maximize brilliance within your budget. Evaluating diamonds on these two separate scales will help you find the perfect centerpiece diamond.