What Makes a Diamond Sparkle? Brilliance, Fire & Scintillation

Light, captured

Three kinds of light

When light enters a diamond it slows down and bends more than in almost any other transparent material. A well-cut diamond catches that light, bounces it between its facets and returns it in three different ways. Jewellers call them brilliance, fire and scintillation.

Brilliance, fire, scintillation

Brilliance
The bright white light reflected back to you. It makes a diamond look alive and luminous.
Fire
Flashes of rainbow colour created when white light splits into its spectral colours, like a prism.
Scintillation
The play of light and dark flashes you see when the diamond, the light or your eye moves.

What decides how much a diamond sparkles

Cut quality. Proportions, symmetry and polish decide how much light returns to your eye. It is the single biggest factor in sparkle.

Shape and facet style. Brilliant cuts produce many small, intense sparkles. Step cuts produce fewer, larger flashes and a mirror-like glow.

Clarity and colour. Clean, colourless diamonds let light travel freely. Our D colour, VVS–VS1 diamonds keep every flash crisp and white.

Lighting. Diamonds sparkle most under direct point light sources, such as spotlights, candles or sunshine. Soft, diffuse daylight shows brilliance, while spotlights reveal fire.

Cleanliness. A thin film of hand cream or skin oil on the pavilion can dull the sparkle noticeably. A quick clean brings it straight back.

Sparkle by shape

Shape	Brilliance	Fire	Character
Round	Highest	High	The benchmark for sparkle
Oval, pear, marquise	Very high	High	Lively brilliant sparkle over a large surface
Cushion	High	Very high	Larger, colourful flashes
Radiant, princess	Very high	High	Crisp, crushed-ice sparkle
Emerald, asscher	Moderate	Moderate	Calm, elegant hall-of-mirrors flashes

Do lab-grown diamonds sparkle like natural ones?

Yes, exactly. Lab-grown diamonds share the same refractive index (2.42) and dispersion (0.044) as natural diamonds. Their sparkle depends on the same thing: the quality of the cut.

How the setting affects sparkle

Open settings, such as slim claws, let more light reach the diamond from the sides. A hidden halo or pavé band adds extra sparkle around the centre stone, while a bezel frames the diamond with a calmer, modern look. You can read more in our guide to setting types.

Keep your diamond sparkling

Clean your ring once a week in warm water with a drop of mild soap and a soft toothbrush, especially underneath the diamond where lotion collects. Put the ring on after creams and perfume, and it will keep its fire for a lifetime.

Made to shine

Cut for maximum light

We choose centre diamonds with excellent cut, polish and symmetry and set them in open, light-filled settings, so your ring sparkles in every room.

Speak with an expert Design your own ring

Frequently asked questions

Why does my diamond look dull sometimes?

Usually because of lotion, soap residue or skin oil on the underside of the stone. A gentle clean restores full sparkle.

Which lighting shows diamonds best?

A mix of daylight for brilliance and point lights, such as candles or spotlights, for fire and scintillation.

Do bigger diamonds sparkle more?

Larger diamonds show broader flashes of fire, but a smaller diamond with an excellent cut can sparkle more than a larger poorly cut stone.

Keep learning

Diamond Anatomy: The Parts of a Diamond Explained
Table, crown, girdle, pavilion and culet: the parts of a diamond, and the proportions that make it shine.
Read the guide
The 4Cs of Diamonds: Cut, Colour, Clarity and Carat
Cut, colour, clarity and carat decide how a diamond looks and what it costs. Here is how each one works, and where it is worth investing.
Read the guide
Engagement Ring Setting Types: How Your Diamond Is Held
Prong, bezel, pavé or channel: how each setting holds your diamond, and what it means for sparkle and security.
Read the guide

The secret of sparkle