Two oval natural diamonds can carry the same carat, colour and clarity grades while looking completely different.
One may appear bright, lively and gracefully proportioned. The other may show a heavy dark bow tie, uneven shoulders and too much weight hidden beneath the girdle.
If both diamonds have GIA reports, neither will currently receive an overall cut grade.
How, then, should a buyer compare them?
The answer is to use the report as a technical filter and the actual diamond as the final decision. Measurements, table percentage, depth percentage, girdle, polish and symmetry provide useful evidence, but they cannot replace an assessment of the diamond’s face-up outline, light performance, contrast, visible spread and movement.
Key Takeaways
- •As of February 2026, GIA gives an overall cut grade only to standard round brilliant diamonds in the D-to-Z colour range.
- •GIA fancy shapes still receive separate polish and symmetry grades.
- •Other laboratories may use different systems. IGI currently offers overall cut grading for fancy shapes.
- •Always inspect the exact report instead of assuming that every laboratory follows the same cut-grading policy.
- •Length-to-width ratio describes the outline; it does not prove good light performance.
- •Table and depth percentages are screening information, not universal approval rules.
- •Polish and symmetry do not equal an overall cut grade.
- •A small bow tie can provide normal contrast, while a large persistent dark area may reduce appeal.
- •Emerald and Asscher cuts should be checked carefully for windowing and uneven step patterns.
- •Carat weight does not reveal face-up size. Compare the millimetre measurements.
- •Extremely thick girdles and excessive depth may hide weight without increasing visual size.
- •Extremely thin girdle areas, exposed points and poorly positioned inclusions can create durability concerns.
- •Compare diamonds of the same shape, facet style and similar length-to-width ratio whenever possible.
- •The final decision should be made from the complete stone rather than one report field.
First Check Which Laboratory Issued the Report
The absence of an overall cut grade has different meanings depending on the grading laboratory.
GIA Reports
GIA’s February 2026 cut-grade guidance confirms that the standard round brilliant is currently the only shape receiving an overall GIA cut grade.
Oval, pear, marquise, cushion, emerald, princess and other fancy cuts do not currently receive an overall cut grade on GIA reports. They are still assessed for polish and symmetry.
This does not mean that GIA considers cut unimportant. It means that the variety of outlines, facet patterns and visual behaviour found across fancy shapes does not currently fit the organisation’s established overall cut-grading system.
IGI Reports
IGI uses a different approach.
Its current fancy-shape cut-grading methodology evaluates polish, symmetry, proportions, craftsmanship and light return before assigning a cut grade ranging from Excellent to Poor.
An IGI fancy-shaped diamond may therefore have an overall cut grade even when an equivalent GIA-graded stone does not.
HRD Antwerp Reports
HRD Antwerp reports can include cut-related information such as proportions, polish and symmetry. The exact information depends on the report type and diamond.
Review the actual document and the laboratory’s current methodology rather than treating cut terminology from different laboratories as automatically interchangeable.
Important Buying Rule
Never compare an “Excellent” label from one laboratory directly with the absence of a grade from another and conclude that the graded diamond is automatically better.
First understand:
- •What the laboratory evaluated
- •Which grading system it applied
- •Whether the grade is overall or limited to one component
- •How the diamond performs during visual inspection
For laboratory differences in more detail, see Dalila’s GIA vs IGI vs HRD comparison.
Fancy Shape and Fancy Colour Are Not the Same
A fancy-shaped diamond is a diamond with a shape or cutting style other than the standard round brilliant. Examples include:
- •Oval
- •Pear
- •Marquise
- •Cushion
- •Radiant
- •Princess
- •Emerald
- •Asscher
- •Heart
A fancy-colour diamond is graded for a colour outside the normal D-to-Z scale, such as Fancy Yellow, Fancy Pink or Fancy Blue.
A diamond can be both fancy-shaped and fancy-coloured, but the two terms describe different characteristics.
This article focuses on fancy shape diamond cut quality, not fancy-colour grading.
What the Report Can and Cannot Tell You
| Report information | What it helps you evaluate | What it cannot confirm alone |
|---|---|---|
| Shape and cutting style | Basic outline and facet family | Whether the outline is attractive |
| Measurements | Length, width, depth and face-up dimensions | Brightness or sparkle |
| Carat weight | Exact weight | Visible size |
| Table percentage | Size of the table relative to the diamond | Overall light performance |
| Depth percentage | How deep the stone is relative to its width | Whether the depth is distributed effectively |
| Girdle | Thickness and possible durability considerations | Complete setting suitability |
| Culet | Size or presence of the bottom facet | Overall cut quality |
| Polish | Surface finish of the facets | Brightness pattern or outline appeal |
| Symmetry | Precision of facet alignment and shape relationships | Whether the diamond is visually beautiful |
| Clarity plot | Position and type of clarity characteristics | Eye cleanliness in every viewing condition |
| Fluorescence | Reaction to ultraviolet radiation | Whether the diamond will look hazy |
| Comments | Treatments, additional characteristics or limitations | Complete face-up performance |
The report narrows the field. The diamond itself determines the final decision.
Dalila’s GIA report-reading guide explains the remaining report fields in more detail.
A Practical Fancy-Shaped Diamond Comparison Process
Step 1: Verify the Report
Use the issuing laboratory’s official verification system, such as GIA Report Check.
Confirm:
- •Report number
- •Report date
- •Natural or laboratory-grown identification
- •Shape and cutting style
- •Measurements
- •Carat weight
- •Colour
- •Clarity
- •Polish
- •Symmetry
- •Fluorescence
- •Inscription
- •Comments
The report details must correspond with the diamond being offered.
Step 2: Compare Diamonds Within the Same Shape Family
Do not compare an oval directly with an emerald cut and try to decide which has “better” cut quality.
Brilliant-style fancy shapes and step cuts handle light differently.
Brilliant-style shapes include:
- •Oval
- •Pear
- •Marquise
- •Cushion brilliant
- •Radiant
- •Princess
- •Heart
These shapes often show more sparkle and faster patterns of light and dark.
Step cuts include emerald, Asscher and baguette diamonds. These shapes produce broader flashes and geometric reflections rather than the faster scintillation expected from brilliant-style diamonds.
Compare like with like: oval with oval, radiant with radiant, emerald with emerald, and cushion brilliant with a similar cushion facet style.
Step 3: Calculate the Length-to-Width Ratio
The length-to-width ratio is calculated as:
Length ÷ Width = Length-to-width ratio
For example:
9.00 mm ÷ 6.00 mm = 1.50
The ratio describes whether a diamond appears:
- •Shorter and wider
- •Square
- •Moderately elongated
- •Long and narrow
It does not grade light performance.
GIA’s oval diamond guide notes that many buyers prefer oval ratios between approximately 1.30 and 1.50, but the most attractive ratio remains a matter of shape preference.
A beautiful oval can fall outside a popular range. A poorly performing oval can fall inside it.
Use ratio to match the desired silhouette, not as a substitute for inspection.
Step 4: Compare Face-Up Dimensions
Carat measures weight, not visible size.
Two one-carat ovals may have different lengths and widths because their weight is distributed differently. One may carry additional weight in:
- •A deep pavilion
- •A thick girdle
- •Bulging pavilion facets
- •A high crown
- •A hidden area below the setting
Compare the millimetre measurements of stones with similar shape, carat weight, length-to-width ratio and facet style.
A diamond that appears unusually small for its weight requires closer investigation.
Larger face-up dimensions are not automatically better either. A shallow diamond may look wide but suffer from poor light return or windowing.
The goal is an attractive balance between spread, light performance and durability.
Step 5: Use Table and Depth as Screening Information
Table and depth percentages help explain how the diamond’s weight and facets are arranged.
They should be used to:
- •Identify unusual proportions
- •Compare similar candidates
- •Investigate hidden weight
- •Understand face-up spread
- •Support visual observations
They should not be used as rigid pass-or-fail rules across every fancy shape.
An oval, cushion, radiant and emerald cut can use different facet arrangements even when their table and depth numbers look similar.
GIA’s research into oval, pear and marquise appearance highlights the range of outlines and visual patterns found within fancy shapes. This variety is one reason visual examination remains essential.
Step 6: Assess the Outline
Outline appeal is one of the most important and least automated parts of fancy-shape evaluation.
Check whether the diamond looks balanced from above.
Look for:
- •Equal left and right sides
- •Properly aligned points
- •Balanced shoulders and wings
- •Consistent corners
- •A centred table
- •A centred culet where visible
- •Graceful curves
- •No unintended bulging or flattening
- •No obvious asymmetry
A grading report may state Excellent symmetry while the buyer still dislikes the overall silhouette. Laboratory symmetry and personal outline appeal are related but not identical decisions.
Step 7: Examine Light Performance
View the diamond face-up under more than one lighting condition.
Check:
- •Brightness across the complete stone
- •Coloured flashes or fire
- •Scintillation during movement
- •Balanced contrast
- •Facet pattern definition
- •Dark areas that disappear as the stone moves
- •Dark areas that remain fixed
- •Transparent or glassy sections
- •Windowing
- •Severe bow ties
- •Dull or inactive areas
A useful diamond video should show face-up view, slow left-to-right movement, forward and backward tilt, side profile, neutral background, diffused light and ordinary viewing distance.
A single highly illuminated photograph can conceal poor performance.
Step 8: Inspect the Girdle and Vulnerable Areas
Check the complete girdle for:
- •Extremely thin areas
- •Excessively thick areas
- •Chips
- •Abrasions
- •Naturals
- •Surface-reaching inclusions
- •Uneven thickness
Pointed shapes such as pear, marquise, princess and heart require particular care.
An inclusion near a point or corner does not automatically make the diamond unsuitable, but it requires professional inspection and an appropriate protective setting.
Step 9: Compare the Total Price
Cut quality influences appearance and commercial desirability even when it is not represented by one overall grade.
Compare:
- •Total diamond price
- •Price per carat
- •Face-up size
- •Shape demand
- •Outline quality
- •Light performance
- •Report laboratory
- •Colour and clarity
- •Durability
- •Suitability for the intended jewellery
- •Resale or retail position
The cheaper diamond is not better value if its poor spread, severe bow tie or unattractive outline makes it difficult to sell.
When comparing face-up size, use Dalila’s diamond sizes in millimetres guide alongside the report measurements.
How to Assess Light Performance Without Special Equipment
Professional optical tools can provide useful information, but buyers can still make a strong initial comparison through structured visual observation.
Look at the Diamond Face-Up
The central area should not appear consistently dull, transparent or inactive.
Brightness should be distributed across the stone rather than concentrated in one small section.
Move the Diamond Slowly
Watch how areas alternate between light and dark.
Healthy contrast helps facets remain visible. A diamond that is uniformly bright under every angle may lack definition, while one that remains dark may have obstruction or leakage problems.
Change the Viewing Distance
Some darkness is caused by the observer blocking light.
GIA’s oval guide explains that a bow tie can appear stronger when the observer moves closer because the head and shoulders block more light.
Evaluate the diamond at a normal jewellery-viewing distance as well as under close inspection.
Check More Than One Light Source
Review the diamond under:
- •Diffused daylight
- •Neutral office-style lighting
- •Spotlighting
- •Mixed ordinary room light
Retail spotlights can make many diamonds sparkle. Diffused lighting is more useful for identifying uneven brightness and persistent dark zones.
Is a Bow Tie Always a Problem?
No.
Oval, pear, marquise and some other elongated brilliant-style diamonds may show a bow-shaped area of contrast across the centre.
A mild bow tie can add contrast and visual structure.
It becomes a concern when it:
- •Appears excessively dark
- •Covers a large central area
- •Remains dark through movement
- •Divides the diamond visually
- •Reduces brightness substantially
- •Distracts immediately at ordinary viewing distance
Do not reject a diamond merely because some bow-tie contrast is visible.
Use Dalila’s bow-tie effect guide for the detailed accept-versus-reject framework on darkness, width, balance and persistence.
What Is Windowing?
Windowing occurs when the observer can see through part of the diamond instead of seeing light reflected back.
It is particularly important in step cuts such as emerald and Asscher diamonds.
To check for windowing:
- •View the diamond face-up.
- •Place it above a neutral surface or printed line.
- •Move and tilt the stone slowly.
- •Check whether the background remains clearly visible through a large central area.
A small amount of transparency at an extreme viewing angle is not the same as major face-up windowing.
A significant window visible when the diamond is viewed normally can weaken its appearance.
How to Evaluate Each Fancy Shape
Oval Diamonds
Inspect:
- •Overall oval balance
- •Left-to-right symmetry
- •Shoulder shape
- •Length-to-width ratio
- •Face-up spread
- •Central bow tie
- •Brightness at the ends
- •Girdle variation
- •Inclusion reflections
Avoid treating the ratio as an automatic quality grade. Two ovals with the same ratio can have different shoulders, facet patterns and bow-tie strength.
Pear-Shaped Diamonds
GIA’s pear-shaped diamond guide recommends checking the outline, shoulders, wings, table position and bow tie.
Inspect:
- •A properly aligned point
- •Balanced shoulders
- •Graceful wings
- •Centred table
- •Even left and right sides
- •Bow-tie strength
- •Brightness through the rounded end
- •Girdle and inclusions near the point
A pear with very rounded shoulders may appear short, while very flat wings may make it look narrow.
Marquise Diamonds
GIA’s marquise buying guide emphasises wing shape, symmetry, points and overall outline appeal.
Inspect:
- •Matching points
- •Equal halves
- •Balanced wings
- •Bow-tie intensity
- •Brightness at both ends
- •Face-up spread
- •Girdle condition
- •Inclusion placement near the tips
The report’s symmetry grade is useful, but the complete outline should still be inspected directly.
Cushion-Cut Diamonds
Cushions vary widely.
They can be:
- •Square
- •Rectangular
- •Elongated
- •Softly rounded
- •More angular
- •Broad-faceted
- •Modified brilliant
- •Crushed-ice in appearance
Compare cushions with similar outlines and facet styles.
Inspect corner consistency, shoulder shape, brightness distribution, central pattern, dark or watery areas, face-up spread, depth, girdle thickness and whether the chosen facet style matches the customer’s preference.
One cushion may show broad, defined flashes while another shows smaller fragmented reflections. Neither style is automatically superior.
Radiant-Cut Diamonds
Inspect:
- •Square or rectangular outline
- •Cropped-corner consistency
- •Central brightness
- •Dark bands
- •Bow-tie appearance
- •Crushed-ice or defined-facet pattern
- •Face-up size
- •Girdle and corner condition
Radiants can show strong sparkle, but some stones have uneven light return or excessive darkness through the centre.
Princess-Cut Diamonds
Inspect:
- •Squareness or intended rectangular shape
- •Equal sides
- •Centred table
- •Brightness through the centre and corners
- •Girdle condition
- •Inclusion placement
- •Corner durability
Princess-cut corners are vulnerable and should normally be protected by an appropriate setting, such as V-shaped prongs.
A princess diamond can look bright while still carrying hidden weight. Compare its face-up measurements with similar candidates.
Emerald-Cut Diamonds
Inspect:
- •Windowing
- •Hall-of-mirrors pattern
- •Parallel step alignment
- •Corner consistency
- •Centred culet
- •Face-up transparency
- •Dark obstruction
- •Symmetry
- •Visible inclusions
- •Face-up spread
Emerald cuts have broad, open facets. Clarity characteristics and weak optical areas may therefore be more visible than in a brilliant-style diamond.
Do not choose an emerald cut through table and depth percentages alone.
Asscher-Cut Diamonds
Inspect:
- •Square outline
- •Cropped corners
- •Centred geometric pattern
- •Concentric step effect
- •Windowing
- •Central darkness
- •Symmetry
- •Face-up spread
- •Visible inclusions
A well-balanced Asscher should show an organised pattern that changes attractively with movement.
Heart-Shaped Diamonds
Inspect:
- •Equal lobes
- •Defined cleft
- •Centred point
- •Symmetry between both halves
- •Balanced wings
- •Central brightness
- •Bow-tie darkness
- •Girdle condition near the cleft and point
Heart shapes are highly sensitive to outline quality. Small asymmetries can noticeably change the intended shape.
Why Polish and Symmetry Are Not Enough
Polish evaluates the surface finish of the facets.
Symmetry evaluates how precisely facets and shape features align.
Both matter, but neither alone measures:
- •Brightness
- •Fire
- •Scintillation
- •Face-up spread
- •Bow ties
- •Windowing
- •Outline appeal
- •Weight distribution
- •Complete durability
- •Customer preference
A fancy-shaped diamond with Excellent polish and Excellent symmetry can still have an unattractive bow tie, poor spread or weak light return.
Treat polish and symmetry as important supporting evidence—not a replacement for overall visual evaluation.
Comparison Worksheet for Trade Buyers
Record the following information for every shortlisted diamond:
| Evaluation field | Candidate A | Candidate B | Candidate C |
|---|---|---|---|
| Laboratory and report number | |||
| Shape and cutting style | |||
| Carat weight | |||
| Measurements | |||
| Length-to-width ratio | |||
| Table percentage | |||
| Depth percentage | |||
| Girdle | |||
| Culet | |||
| Polish | |||
| Symmetry | |||
| Face-up spread | |||
| Outline appeal | |||
| Brightness | |||
| Bow tie or dark zones | |||
| Windowing | |||
| Scintillation during movement | |||
| Durability concerns | |||
| Eye cleanliness | |||
| Total price | |||
| Price per carat | |||
| Final decision |
Use the same video conditions and comparison standards for every candidate.
Warning Signs That Require Closer Inspection
Pause before approving a fancy-shaped diamond when you see:
- •Report information that does not match the stone
- •Severe persistent bow-tie darkness
- •Large face-up windowing
- •Extensive dead or watery areas
- •Noticeably uneven outline
- •Misaligned point or culet
- •Unequal shoulders, wings, lobes or corners
- •Very poor face-up size for the carat weight
- •Extremely thin vulnerable girdle areas
- •Chips or abrasions
- •Surface-reaching inclusions near points or corners
- •Inclusion reflections across multiple facets
- •Transparency or haziness concerns
- •Excessive colour concentration in one area
- •A video that hides the side profile or movement
- •A price that assumes premium cut quality without evidence
These signs do not always require automatic rejection. They require explanation, professional inspection and appropriate pricing.
Common Buying Mistakes
Applying Round-Diamond Proportion Rules
Fancy shapes do not use one standardised round brilliant facet arrangement. Round “ideal proportion” charts should not be applied universally.
Buying from Table and Depth Alone
Similar percentages can produce different outlines and light patterns.
Treating Excellent Symmetry as Excellent Overall Cut
Symmetry is one component, not a complete assessment.
Assuming Every Laboratory Uses the Same System
GIA and IGI currently handle fancy-shape cut grading differently.
Ignoring Millimetre Measurements
Carat weight can be hidden in depth or girdle thickness.
Rejecting Every Bow Tie
Some contrast is normal. The concern is excessive, distracting and persistent darkness.
Comparing Different Facet Styles
A crushed-ice cushion and a broad-faceted cushion should not be judged as though they are intended to look identical.
Trusting One Photograph
A still image can hide bow ties, windowing, obstruction and weak scintillation.
Ignoring Setting Requirements
Points, corners and vulnerable girdle areas must suit the planned jewellery design.
Fancy-Shaped Diamond Buying Checklist
Before purchasing, verify:
- •Report authenticity
- •Natural or laboratory-grown identification
- •Report number and inscription
- •Shape and cutting style
- •Measurements
- •Carat weight
- •Length-to-width ratio
- •Table percentage
- •Depth percentage
- •Girdle thickness
- •Culet
- •Polish
- •Symmetry
- •Fluorescence
- •Clarity plot
- •Report comments
- •Face-up spread
- •Outline balance
- •Shoulder and wing shape
- •Point and corner alignment
- •Brightness
- •Fire
- •Scintillation
- •Contrast pattern
- •Bow-tie strength
- •Windowing
- •Dark or dead zones
- •Inclusion reflections
- •Transparency
- •Surface-reaching inclusions
- •Girdle condition
- •Setting suitability
- •Total price
- •Price per carat
- •Customer preference
- •Final professional inspection
An Antwerp Sourcing Perspective
Fancy-shaped natural diamonds require more individual review than a spreadsheet filter can provide.
Measurements and grading information can reduce the shortlist, but videos and professional inspection help identify differences in outline, spread, bow ties, windowing, transparency and overall face-up appeal.
Through Dalila Diamonds’ Secure to Source service, jewellers and trade buyers can submit a sourcing request by shape, carat, colour, clarity, ratio and budget, then receive quality-control support before the selected stones are delivered.
Buyers can also browse the natural-diamond inventory and compare available diamonds by shape and certification.
Dalila’s Diamond Knowledge Guide provides an overview of shapes, the 4Cs and certification.
Final Answer: How Should You Compare Fancy-Shaped Diamonds?
When the grading report has no overall cut grade, do not attempt to create one from a table-and-depth chart.
Use the report to confirm:
- •Identity
- •Measurements
- •Proportions
- •Finish
- •Clarity
- •Durability information
Then use direct visual comparison to judge:
- •Outline
- •Face-up size
- •Brightness
- •Contrast
- •Scintillation
- •Bow ties
- •Windowing
- •Overall appeal
Compare stones within the same shape and facet family under identical viewing conditions.
The best fancy-shaped diamond is not necessarily the one with the highest polish and symmetry grades or the most popular length-to-width ratio. It is the stone that combines an attractive outline, balanced light performance, suitable spread, safe construction, reliable documentation and a fair price.