Botswana's remarkable Karowe Diamond Mine has added yet another glistening chapter to its history with the recovery of an astonishing 1,305.4-carat rough diamond — a gem weighing more than half a pound that now ranks as the sixth-largest rough diamond ever unearthed and the fifth-largest ever discovered in Botswana.
The newly recovered white diamond measures an impressive 79.9 millimeters by 34.1 millimeters by 51.9 millimeters and marks the 10th diamond exceeding 1,000 carats recovered by Lucara Diamond Corp. since production began at Karowe in 2012.
With this latest discovery, Karowe further cements its extraordinary reputation. An astonishing 11 of the 13 largest rough diamonds ever found have originated from this single Botswana mine, including the 2,492-carat Motswedi (#2 all time), the 2,036-carat unnamed diamond, the 1,758 carat-Sewelô, the 1,476-carat unnamed diamond, the 1,111-carat Lesedi La Rona, the 1,094-carat Seriti and the 1,080-carat Eva Star.
Only one diamond still towers above them all: the legendary 3,106-carat Cullinan Diamond, discovered in 1905 at South Africa's Premier Mine. The giant crystal was eventually cleaved into nine principal polished diamonds and nearly 100 smaller stones. Two of the most famous — Cullinan I, the 530.2-carat Great Star of Africa, and Cullinan II, the 317.4-carat Second Star of Africa — today reside among the British Crown Jewels.
Lucara credits its success to cutting-edge Mega Diamond Recovery (MDR) X-ray Transmission (XRT) technology, which is specifically designed to preserve exceptionally large diamonds.
Unlike older recovery methods that relied on crushing ore into smaller pieces, the XRT system scans rocks traveling on conveyor belts using powerful X-rays. Sophisticated sensors analyze the atomic density of each rock, allowing the system to distinguish carbon-based diamonds from surrounding kimberlite. When a diamond is detected, computerized air jets instantly blast it off the conveyor into a separate collection bin — allowing valuable stones to be recovered intact before they can be damaged.
The technology has revolutionized the recovery of giant diamonds and has been instrumental in nearly all of Karowe's headline-making discoveries.
"The recovery of our 10th diamond exceeding 1,000 carats is another extraordinary milestone for Karowe," said Lucara President and CEO William Lamb, noting that no other diamond mine has consistently produced stones of this magnitude.
The latest diamond was recovered while processing a blend of current open-pit ore and previously stockpiled material, making it impossible to determine exactly where within the orebody it originated.
Karowe's future also looks exceptionally bright. The mine is currently transitioning from an open-pit operation to an underground mine designed to access the highest-value portion of the kimberlite deposit. Underground ore is expected to begin replacing stockpiled material in 2027, with full-scale underground production scheduled for the first half of 2028.
Credit: Image courtesy of Lucara Diamond Corp.