Most Expensive Diamonds No. 1 - The Koh-i-Noor - Monroe Yorke Diamonds
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Most Expensive Diamonds No. 1 - The Koh-i-Noor

A clear, expert guide from the Monroe Yorke Diamonds team.

By Sandy Maxwell Updated June 2026 1 min read

Understandably, the pinnacle of the list of the world's most expensive diamonds is the fabulous Koh-i-Noor, The Mountain of Light, a diamond so valuable a price will probably never be estimated for its financial worth.

The diamond was once known as the largest diamond in the world, and is definitely considered by gemmologists as the most precious at 105.6 carats (21.6 grams)

This stunning gem is said to have been discovered in the Andhra Pradesh Region of India, along with its double, the beautiful Darya-ye-Noor - known as the Sea of Light.

The stone has belonged to various owners, Hindu, Rajput, Mughal, Iranian, Afghan, Sikkh and British rulers who fought over this fabulous gem which was often seized as a spoil of war.

When Queen Victoria became the Empress of India, the Koh-i-Noor became part of the British Crown Jewels and is still owned by British Royal family, currently set in the Coronation Crown as seen above.

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Written & reviewed by the Monroe Yorke Diamonds team

We have spent 20 years helping Australians choose diamonds, with appointment-only studios in Sydney, Melbourne, Brisbane and Perth.

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