Diamond Shapes Explained by a Master Jeweller: The Complete Guide 2026

This chart helps customers visualise differences in shapes as carat increases. 

Round Brilliant Diamond

Overview

The Round Brilliant Cut is the most iconic and technically precise of all diamond shapes. Engineered with 57–58 facets, it’s designed to maximise light return, fire, and scintillation, making it the unrivalled choice for brilliance. Because of its symmetrical geometry and ability to mask minor inclusions, the Round Brilliant remains the global benchmark for sparkle and optical performance. Its balanced shape suits nearly every hand, every style, and every setting.

Pros

• Maximum brilliance and fire
• Works with any setting
• Universally flattering
• Strict cut grading, making it easier to choose a beautiful stone

Cons

• Highest price per carat
• Looks smaller than ovals/pears or the same carat weight

Best For 

Timeless engagement rings, pavé bands, classic solitaires.

Master Jeweller Notes

The Round Brilliant is the most technically demanding diamond shape because its performance relies heavily on precise mathematics. Small deviations in cut grade dramatically affect brightness. At Armans, we inspect each stone for crown height, pavilion depth, lower-half facet length, and table-to-depth ratios to ensure it performs at its absolute peak.

This shape is versatile in settings, but we most often recommend:

• 4 or 6 prong solitaires to showcase the perfect symmetry
• Hidden halos for enhanced radiance without altering the classic appearance
• Cathedral settings for added height and elegance

A premium cut Round Brilliant will often look smaller on the finger than elongated shapes, but it makes up for it with unmatched light return. If brilliance is your priority, nothing surpasses this shape.

Oval Diamond

Overview

The Oval Cut offers a graceful silhouette with an elongated profile that creates the illusion of a larger diamond. Its modified brilliant facet pattern delivers strong sparkle while also lengthening the appearance of the finger. The oval’s flattering proportions and modern-meets-classic aesthetic make it one of the most sought after shapes in Australia today.

Pros

• Looks bigger than round of the same carat weight
• Slenderising, elongates the finger
• Modern yet timeless
• Great brilliance

Cons

• Some stones display bow-tie
• Requires careful ratio selection

Best For: Modern solitaires, hidden halos, organic designs. 

Master Jeweller Notes

Bow-tie in ovals is normal. The key is achieving a soft, blended bow rather than harsh dark lines. We hand select stones with optimal facet symmetry to minimise this. 

Cushion Cut Diamond

Overview

The Cushion Cut is known for its soft, pillow-like shape and romantic, antique inspired character. With variations including brilliant, modified brilliant, and antique cut patterns, the cushion offers deep sparkle and gentle curves. Its versatility makes it suitable for both vintage and contemporary designs.

Pros

• Often the best value per carat 
• Beautiful vintage appeal
• Soft, glowing sparkle
• Versatile design options

Cons

• Looks smaller than oval/pears
• Very variable in cut style

Best For: Vintage lovers, halos, romantic designs.

Master Jeweller Notes

Cushions have no standardised facet pattern, meaning two 1ct cushions can look totally different. We examine depth %, table %, and facet alignment closely. 

Emerald Diamond

Overview

The Emerald Cut features an elegant rectangular shape with step-cut facets that produce a hall-of-mirrors effect rather than traditional sparkle. The long, linear facets create dramatic flashes of light and a refined, architectural feel. The Emerald Cut is a favourite among those who appreciate sophistication, clarity, and unmistakable presence.

Pros

• Looks larger than round
• Mirror-like flashes rather than sparkle
• Sophisticated and understated
• Excellent for bezel settings

Cons

• Inclusions are more visible
• Requires high clarity

Best For: Minimalists, art deco styles, thick gold bands.

Master Jeweller Notes

Always prioritise clarity in emerald cuts. We recommend VS1 or better for a truly clean appearance. 

Radiant Diamond

Overview

The Radiant Cut blends the brilliance of a Round with the geometry of an Emerald or Princess, thanks to its hybrid facet pattern. It is one of the most sparkling elongated shapes, with clipped corners and deep facets that create intense fire. Radiant cuts appear larger than most other shapes of the same carat weight due to their substantial face up spread.

Pros

• Huge sparkle
• Hides inclusions well
• Works in rectangular or square form
• Great for halos and solitaires

Cons

• Can appear smaller than ovals
• Less common

Best For: Brides wanting brilliance without a round or oval. 

Master Jeweller Notes

Radiant cuts vary more than any other shape, especially in facet style, depth, and length-to-width proportions. We hand select stones with strong corner symmetry, low bow-tie presence, and consistent light distribution.

Pear Diamond

Overview

A tear drop combination of round and marquise cuts. Its teardrop silhouette creates dramatic finger lengthening and exceptional sparkle when well proportioned. Pear cuts are expressive, feminine, and highly distinctive.

Pros

• Very elongating
• Appears large for carat
• Unique without being too bold
• Bright and brilliant

Cons

• Bow tie risk
• Needs protective setting on tip

Best For: East west designs, vintage designs, bold solitaires. 

Master Jeweller Notes

The point of a pear is vulnerable. We always recommend a V prong or bezel tip for security.

Marquise Diamond

Overview

The Marquise Cut features a long, slender body with pointed ends, creating one of the most elongated silhouettes in fine jewellery. Its design maximises carat spread, often looking significantly larger than other shapes of equal weight, and offers dramatic, elegant finger coverage.

Pros

• Biggest looking of all shapes
• Accentuates finger length
• Very elegant and dramatic

Cons

• Tips require protection
• Symmetry is crucial
• Can show bow-tie

Best For: Vintage lovers, bold styles, east west rings.

Master Jeweller Notes

We pay special attention to shoulder symmetry. Even a slightly uneven marquise will look “off” on the hand. 

Princess Diamond

Overview

A modern, geometric square diamond known for sharp lines, bright sparkle, and a contemporary aesthetic. Particularly popular for those who prefer a clean, structured look.

Pros

• Sharp, clean aesthetic
• Strong sparkle for a square shape
• Typically good value

Cons

• Corners chip without protective settings
• Less popular in recent years
• Deeper stone which means it has a smaller face up appearance

Best For: Contemporary design lovers, channel set engagement rings, minimalist style, those wanting a non-round shape that still sparkles strongly. 

Master Jeweller Notes

Princess cuts have four pointed corners, which makes durability a key consideration. We always ensure claws cover every corner securely. When selecting a stone, we look for even, symmetrical chevron patterns in the pavilion as this is what gives the princess its “crushed ice vs brilliant” look. 

Asscher Diamond

Overview

A sophisticated, art-deco inspired square step cut diamond with cropped corners and mesmerising hall-of-mirrors reflections. Often described as the “square emerald cut”, but often with its own personality and dramatic light performance. 

Pros

• Vintage, architectural elegance
• Unique optical effect (hall-of-mirrors)
• Distinctive geometric look
• Excellent in bezel and solitaires
• Truly timeless for deco lovers

Cons

• Shows inclusions more easily
• Lower brilliance than brilliant cuts
• Appears smaller due to depth
• Very specific aesthetic (not for everyone)

Best For: Art Deco inspired designs, vintage ring lovers, bold solitaires, thick 18ct gold bands.

Master Jeweller Notes

Asscher cuts demand exceptional clairty. Because the step facets act like windows, inclusions are more visible compared to brilliant cuts. We recommend VS1 or higher for a clean appearance. 

The key to a top tier asscher is its depth, symmetry and windmill patterns. A well cut asscher should show clear, balanced “x” windmills when viewed from above. We hand select stones that have strong light reflection and crisp facet lines - poorly cut asschers appear dull or glassy. 

• Choosing by carat instead of mm size
• Selecting fancy shapes without checking bow-tie severity
• Choosing emerald cuts with low clarity 
• Forgetting that shape changes how large a stone appears
• Assuming all cushion cuts look the same
• Prioritising colour over cut quality