Lucara Botswana Proprietary Limited, an indirect, wholly-owned subsidiary of the Lucara Diamond Corp. and the 100% owner of the Karowe Mine.
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Summary:
Deposit Types
The primary source rocks for diamonds currently being mined or that have been mined worldwide are kimberlites, orangeites and olivine lamproites. The vast majority of primary diamond deposits mined globally consist of steep-sided, pipe-shaped bodies infilled with volcaniclastic kimberlite (Scott Smith et al., 2013, 2018). Less common are diamond mines hosted in hypabyssal kimberlite and orangeite dykes or sills (intrusive sheets) and in pipes comprised entirely of coherent kimberlite.
Kimberlites are mantle-derived (>150 km depth), volatile-rich, ultramafic magmas that transport diamonds together with the rocks from which the diamonds are directly derived (primarily peridotite and eclogite) to the earth’s surface. They are considered to be hybrid magmas comprising a mixture of incompatible-element enriched melt and ultramafic material from the lower lithosphere that is incorporated and partly assimilated into the magma.
Mineralization
KDM is one of the world’s most significant producers of large and high-value diamonds including fine-gem Type IIa and rare coloured diamonds. From inception to the end of Q3 2025, Karowe has recovered 43 diamonds > 300 ct, 69 diamonds between 200 and 300 ct, and 283 diamonds between 100 and 200 ct. The mine has recovered nine diamonds in excess of 1,000 ct since 2015. The South Lobe has consistently recovered high-value diamonds in excess of 200 ct and several of the Legacy stones (Section 14) have come from the EM/PK(S), including the 1,109 ct Lesedi La Rona.
The M/PK(S) and EM/PK(S) each have distinct diamond grades, size frequency distributions (SFD), average US$/ct diamond values and significant stone recoveries (Section 14). The SFDs are considered as coarse with roughly 60 to 70% of the mine’s revenue being generated by +10.8 ct diamonds (Specials) that make up greater than 6% of the carats produced.
Since 2012, the mine has produced over 290,000 ct and over 9,000 stones in excess of 10.8 ct for an average stone size of 30.9 ct/stn for the +10.8 ct production. In the period from 2015 to September 30, 2025 inclusive, the mine has averaged 6.4 wt% of total production being >10.8 ct in weight, and 7.5 wt% of M/PK(S) and EM/PK(S) production. The nine stones exceeding 1,000 ct include a 1,174 ct diamond recovered in 2021, a 1,080 ct diamond recovered in 2023, and the 2,488 ct Motswedi and 1,094 ct Seriti recovered in Q3 2024.
composition of their mineral inclusions (Motsamai et al., 2018): 53% of Karowe inclusion-bearing diamonds are derived from eclogitic sources, 44% are peridotitic, 2% have a sublithospheric origin, and 1% are websteritic. A sublithospheric inclusion suite was established by eclogitic garnets containing a majorite component, a feature so far unique within the Orapa kimberlite cluster (Motsamai et al., 2018). The origin of the majorite-bearing diamonds is estimated to be between 330 to 420 km depth, straddling the asthenosphere–transition zone boundary. The observation of superdeep mineral inclusions in Karowe diamonds is consistent with a sublithospheric origin for the exceptionally large diamonds.