Historic Diamond Fields & Mines in Lesotho
Letšeng — High-Value Kimberlite at High Altitude
Perched above 3,000 m in the Maloti, Letšeng is famed for an unusually high frequency of large, Type IIa white diamonds and industry-leading $/ct values. Since Gem Diamonds restarted operations, record stones (often 100+ ct) have reinforced Letšeng’s reputation. Sources: GIA, Letšeng’s Unique Diamond Proposition; Gem Diamonds releases.
Liqhobong — Firestone’s Northern Highlands Mine
Brought to commercial production in 2016, Liqhobong is a large open-pit kimberlite operation. Though more of a volume producer than Letšeng, it periodically yields “specials,” including a 215 ct rough recovered in 2024. Sources: Firestone Diamonds, Liqhobong overview; IDEX, 215-ct recovery (Mar 6, 2024).
Kao — Storm Mountain Diamonds (noted for pinks)
The Kao kimberlite (Lesotho’s largest pipe) produces high-quality whites and rare fancy-color diamonds, notably large pinks. Capacity upgrades in recent years increased throughput and underpinned headline recoveries, including a 108.39 ct pink in 2023. Sources: SMD, Kao Mine; National Jeweler report on the 108.39 ct pink (Apr 24, 2023).
Mothae — Lucapa’s Large-Stone Producer
Adjacent to Letšeng, Mothae is another high-value kimberlite noted for large Type IIa D-color stones. XRT-based flowsheets target recovery of big, unbroken crystals and have delivered multiple 100+ ct roughs. Sources: MiningDataOnline, Mothae snapshot; TOMRA mining note (May 7, 2024).
Lesotho’s Most Historic & Largest Diamonds
Lesotho Legend (Letšeng)
Rough: 910 ct, D-color Type IIa; recovered Jan 2018. Notes: Sold for ~US$40M; later cut by Van Cleef & Arpels into 67 diamonds totaling 441.75 ct for its Legend of Diamonds collection. Sources: Gem Diamonds sale notice (Mar 13, 2018); Van Cleef & Arpels project page.
Letšeng Star
Rough: 550 ct (Aug 2011), Type IIa, D-color; sold via profit-share arrangement. Notes: One of the largest white rough diamonds on record. Sources: Gem Diamonds 2011/2012 updates; company “Famous Diamonds” page.
Letšeng Legacy
Rough: 493 ct (Sep 2007); sold in Antwerp for US$10.4M. Notes: Ranked among the largest rough diamonds globally at the time. Sources: Investegate (Nov 5 & 14, 2007); Reuters recap.
Light of Letšeng
Rough: 478 ct (2008); sold for US$18.4M to SAFDICO (Graff). Notes: Another marquee Letšeng recovery from the modern era. Sources: Letšeng Diamonds customer page; RTT News (2008).
Lesotho Promise
Rough: 603 ct (Aug 22, 2006), D-color; sold for US$12.4M; cut into 26 stones totaling ~224 ct (largest 75 ct pear). Source: Wikipedia “Lesotho Promise” (with sale & cutting details); GIA background notes.
Lesotho (a.k.a. “Lesotho Brown”)
Rough: 601 ct (May 1967), discovered by Ernestine Ramaboa near Letšeng; cut into 18 polished stones (largest ~71.7 ct). Sources: InternetStones / NaturallyColored profiles (origin, discoverer, cutting).
Kao 108.39-carat Pink (Kao)
Rough: 108.39 ct fancy pink (Mar 2023), among the largest pink roughs found in Africa; announced by Storm Mountain Diamonds. Sources: National Jeweler; Mining.com report; SMD site.
Summary
Lesotho’s story is kimberlite-driven and altitude-defined: compact open pits on the Maloti plateau produce outsized, top-type diamonds. From Letšeng’s run of giants—the 910 ct Lesotho Legend, 550 ct Letšeng Star, 493 ct Letšeng Legacy, and 478 ct Light of Letšeng—to Liqhobong’s and Mothae’s big Type IIa whites and Kao’s rare large pinks, the kingdom commands a share of modern diamond history disproportionate to its size. Primary references: GIA Letšeng overview; Gem Diamonds, Firestone, Storm Mountain Diamonds, Lucapa company materials and trade press.
For information on famous diamonds, visit our Diamond Page.Datasets: U.S. Geological Survey, Major Mineral Deposits of the World, Open-File Report 2005-1294. Data portal