Cullinan I


Weight: 530.2 carats

Dimensions: 58.9 x 45.4 x 27.7 mm

Color: Colorless

Weight of Rough: 3,106 carats

Origin: Premier Mine, South Africa

Date Found: 1905

Current Location: Tower of London; British Crown Jewels


The nine Cullinan diamonds are the result of a remarkable piece of rough weighing 3,106 carats found in the Premier Mine, South Africa, in 1905. This stone was cut into nine major stones and 96 smaller stones. The Cullinan I and II are a part of the British Crown Jewels. The Cullinans III – IX actually belong to the Queen, and in some circles are referred to as “Granny’s Chips.”

Photographs of the Cullinans are fairly common, being reproduced all over the Internet and in many books. Various weights given for the stones are equally widespread. However, the dimensions are not reported anywhere, not even among the staff at the Tower of London or Royal Collections.

The dimensions used in creating my replicas originally came from a series of articles by Tom Barbour published in the 1960’s in Lapidary Journal. These have been proven wrong as the dimensions listed here came from the Crown Jeweler and Asscher diaries.  Barbour reported the dimensions of his replicas, not the original stone, and these have been erroneously propagated all over the Web.

Cullinan I

Up until a few years ago, The Cullinan I was the world’s largest diamond at 530.20 carats. Now it is #2, behind the Golden Jubilee at 545.67 carats.

Erroneous information has been posted on the Web concerning the size of the Cullinan I. Per the Collections Curator at the Natural History Museum in London, and per the Crown Jeweler, the Cullinan I dimensions are 58.9 x 45.4 x 27.7 mm. These are accurate when modeled, and the L:W ratio is verified by the photos.