SIENNA AI
Origin

The Story of Brown Diamonds

The result is a remarkable spectrum of natural colour, shaped underground over millions of years. This is how brown diamonds come to be.

Brown diamond
01

Naturally expressive

Brown diamonds are among the most naturally expressive diamonds found on Earth. Their colour is not added, treated, or enhanced. It is created during the diamond’s formation itself.

02

Shaped by pressure

Beneath the Earth’s surface, immense pressure subtly alters the crystal structure of a diamond. As light travels through the stone, these microscopic changes create the warm tones that make each brown diamond unique.

03

One of a kind

Some diamonds appear soft and golden, while others display rich amber and cognac hues. No two stones are ever exactly alike. Every brown diamond is a record of the forces that shaped it over millions of years.

The Argyle Mine

A Legacy from Argyle

Scroll through the chapters of the brown diamond legacy.

Origins

Where the story begins

Much of the modern brown diamond story begins with Argyle.

History

The Argyle Mine

The Argyle Mine produced the majority of the world’s brown diamonds. Located in the remote East Kimberley region, Argyle became one of the most significant diamond mines ever discovered. The very same mine was also home to most of the world’s pink diamonds.

Grading

A shared language

Argyle introduced the terminology and colour classifications that helped define the brown diamond market. Its grading scale established a common language for describing brown diamonds and remains widely recognised throughout the industry today.

Closure

Chapter closes

When the Argyle Mine closed permanently, it marked the end of an important chapter in brown diamond history.

A Spectrum of Colour

A Spectrum of Colour

Brown diamonds exist across an extraordinary range of shades. Tap each grade to explore the spectrum.

C1 brown diamond
Champagne

C1 · AIR

The lightest end of the spectrum. Soft golden warmth and the entry point to the brown diamond colour story.

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Desert DiamondsAll shades

De Beers introduced the term Desert Diamonds for the broader family of warm earth-toned natural diamonds, from the lightest Champagne to the deepest Cognac.

C1–C4

Champagne

The lighter end of the spectrum, commonly associated with Champagne diamonds, known for their soft golden warmth.

C5–C6

Chocolate

Richer brown tones often described as Chocolate diamonds. The term was popularised by luxury jeweller Le Vian.

C7–C8

Cognac

The deepest shades, prized for their richness, depth, and character. Rarer and finite since the mine’s closure.

545.67carats
The Golden Jubilee

One notable diamond in the history of brown diamonds is the Golden Jubilee. At 545.67 carats, it is the largest faceted diamond in the world. Its extraordinary size and warm golden-brown colour have secured its place among history’s most celebrated diamonds.

Jewellery history

The Rise of Brown Diamonds

Through the centuries

Brown diamonds have appeared throughout jewellery history for centuries, but appreciation for their natural colour has only grown significantly over the last few decades.

Today

Today, collectors, designers, and consumers are increasingly drawn to diamonds with individuality and character. These brown diamonds therefore represent one of nature’s most diverse and captivating colour stories.

Every stone carries subtle differences in tone, depth, and expression, making each one entirely its own.

Continue the Journey

Enter the Spectrum

Discover the world of natural brown diamonds, available in every shade from C1 to C8

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