They did it again.
The Letšeng Diamond Mine in Lesotho has recovered two more 100+ carat diamonds — a 100.71-carat Type I faint yellow diamond and a 191.84-carat Type IIa colorless diamond — continuing the mine’s remarkable record of producing some of the world’s most important large rough diamonds.
The recoveries were announced this month by Gem Diamonds in a quarterly update reported by Mining Weekly.
Make no mistake — a 100-carat diamond remains an extraordinary discovery.
Among the more than 100 million carats of rough diamonds recovered globally each year, only a tiny fraction exceed 100 carats.
Yet Letšeng continues to find them.
Not because they are common. Far from it.
But because this remarkable mine has developed a habit of producing some of the world’s most exceptional large rough diamonds.
What makes Letšeng especially remarkable is not simply the occasional giant diamond.
It is the consistency.
Images courtesy of Gem Diamonds
Over just the past two years, the mine has reported an astonishing sequence of large diamond recoveries, including:
- a 319.40-carat diamond in October 2025
- a 295-carat Type IIa colorless diamond in January 2024
- a 212.91-carat Type II colorless diamond in September 2024
- a 212.49-carat Type II colorless diamond in May 2024
- two light brown diamonds weighing 194.52 carats and 109.95 carats in April 2025
- a 193.07-carat Type II colorless diamond in January 2026
- a 172.06-carat Type II colorless diamond in June 2024
- a 169.15-carat Type II colorless diamond in April 2024
- a 154.90-carat Type II colorless diamond in October 2025
- a 145.55-carat Type II colorless diamond in August 2024
- and a 101.14-carat diamond recovered in February 2026, only weeks after the 193-carat recovery.
Looking at the list, it is easy to become accustomed to these announcements. That would be a mistake. Each of these recoveries represents an exceptionally rare event in the global diamond industry.
The list also includes multiple additional 100+ carat diamonds, Type I stones, brown diamonds, and a number of pink diamonds recovered over the years in varying sizes and qualities.
At many mines, a single gem-quality 100-carat diamond would become a historic event.
At Letšeng, the big ones just keep on coming.
So How Does This Happen?
Part of the answer is geology.
According to a landmark study published in Gems & Gemology by the Gemological Institute of America, Letšeng has become famous for producing large Type IIa colorless diamonds with exceptionally high dollar-per-carat values.
The mine has long been known for recovering unusually large high-quality rough from relatively low-grade ore — meaning comparatively few diamonds overall, but a disproportionate number of very important stones.
But geology is only part of the story.
Letšeng’s recovery process combines several technologies. Ore is first processed through a Dense Media Separation (DMS) circuit before entering the recovery stage, where advanced XRT systems from both Steinert and TOMRA help identify and recover diamonds from the processed material.
Together, these technologies form part of a sophisticated recovery process designed to maximize diamond recovery while handling some of the world’s most valuable rough.
Unlike traditional X-ray luminescence systems, XRT technology identifies materials through differences in X-ray transmission characteristics, making it a valuable tool in modern diamond recovery operations.
According to TOMRA Mining, Letšeng became home to the world’s first TOMRA COM XRT Final Recovery sorter installation. Today, the mine’s recovery circuit incorporates advanced recovery technologies from multiple suppliers, including both TOMRA and Steinert, reflecting Letšeng’s broader emphasis on recovery efficiency and diamond recovery optimization.
While luck always plays a role in diamond mining, Letšeng’s remarkable record of large diamond recoveries reflects far more than chance. It is the product of extraordinary geology combined with sophisticated recovery methods.
Lesotho, Africa
Why This Matters to the Trade
While exceptional natural diamonds continue to command strong interest and premium prices, they have not been completely immune to recent market pressures. However, the impact has generally been less severe than that experienced by lower-value, smaller commercial rough diamonds.
In its latest quarterly report, Gem Diamonds noted that four diamonds sold for more than $1 million each during the quarter. The company also reported a highest achieved price of $32,908 per carat for a 52.24-carat colorless diamond.
Even more notable, average realized prices rose 17% year-over-year to $1,501 per carat, supported by the sale of large, high-value diamonds.
That tells us something important:
The market for exceptional rough diamonds continues to behave differently from the broader commercial market.
Rare large rough still attracts attention.
Exceptional diamonds remain highly sought after.
And at Letšeng, the big ones just keep on coming.
