What Is The Largest Diamond In The World?

At Plateau Jewelers, nestled in the heart of Sammamish, WA, we're passionate about sharing the tales and treasures of the earth's most coveted creations. Today, we invite you on a journey to discover the king of diamonds—the Cullinan Diamond. Known as the largest diamond to ever grace our planet, its legacy goes beyond its astonishing size, reflecting a saga of human ingenuity and the pursuit of perfection. 

Join us as we delve into the heart of this luminous legend, illuminating the facets of its history, its remarkable journey from mine to masterpiece, and how it continues to sparkle in the crown jewels of royalty.

The Title of The Largest Diamond

The title of the largest diamond in the world goes to the Cullinan Diamond. This gem is unmatched in size and brilliance. It was discovered in 1905 in the Premier No. 2 mine near Pretoria, South Africa. The Cullinan Diamond weighed an astonishing 3,106.75 carats (621.35 grams or approximately 1.37 pounds) in its rough state. This made it the largest rough diamond ever found.

Discovery and History

The Cullinan Diamond was named after Sir Thomas Cullinan, the owner of the mine where it was found. Its discovery garnered worldwide attention. This was not only because of its unprecedented size but also due to its exceptional quality and clarity. The Transvaal Colony government bought the diamond. They gifted it to King Edward VII of the United Kingdom as a token of loyalty. It was also part of the celebrations for his 66th birthday.

Cutting and Division

Cutting the Cullinan Diamond was a huge responsibility because of its size and value. The task went to Joseph Asscher and Co. in Amsterdam. They were known for their skill in cutting large diamonds. After months of study, Joseph Asscher cleaved the diamond into two main parts on his first attempt. Further cutting and polishing yielded 9 major stones and 96 smaller brilliants.

The Cullinan I: The Great Star of Africa

The largest of these stones is the Cullinan I, or the "Great Star of Africa." It weighs 530.2 carats and is the largest clear-cut diamond in the world. This pear-shaped diamond is mounted in the head of the Sovereign’s Sceptre with Cross. This is part of the British Crown Jewels.

The Cullinan II: The Second Star of Africa

The second-largest stone, the Cullinan II or the "Second Star of Africa," weighs 317.4 carats. This rectangular cushion-cut diamond is set in the front of the Imperial State Crown. This crown is also a part of the British Crown Jewels.

The Legacy

The remaining stones, known as Cullinan III through Cullinan IX, are smaller but equally magnificent. They are part of the personal collection of the British royal family. These stones have been set into various royal artifacts, including brooches, necklaces, and crowns. Each carries a piece of history and the legacy of the Cullinan Diamond.


The Cullinan Diamond's discovery and its transformation into precious jewels is a story of craftsmanship and history. Its division into several pieces allowed its legacy to spread across various artifacts. Each tells a part of the remarkable journey of the world's largest diamond. Today, the Cullinan diamonds remain a symbol of luxury, royal heritage, and human artistry and ingenuity in gemstone cutting.

Curious to learn more about the fascinating world of diamonds and luxury jewelry? Let’s dive deeper together. Visit Plateau Jewelers in Sammamish, WA, and explore our exquisite collection of fine jewelry. Whether you’re looking to admire the craftsmanship behind every piece or find that perfect jewel to call your own, we're here to guide you through the journey with expertise and care.