Gemfields Unveils ‘Imboo’, an 11,685-Carat Emerald from Kagem Mine
Gemfields has unveiled its latest extraordinary find at Kagem Mining – an 11,685-carat emerald named Imboo, meaning “buffalo” in Bemba and Lamba. Weighing 2.337 kilograms, the stone is the largest of exceptional quality to be discovered at the world-renowned mine in Zambia’s Copperbelt Province.
The gemstone, recovered from the Chama pit on 3 August 2025, will be showcased at Gemfields’ high-quality emerald auction running until 11 September, with all proceeds repatriated to Zambia. Kagem is majority-owned and operated by Gemfields in partnership with the Zambian government through the Industrial Development Corporation (IDC).
“In my thirty years at Kagem, I’ve rarely seen such a remarkable formation of large, high-quality crystals,” said Jackson Mtonga, Grading Manager at Kagem. “The immense size and nature of the crystal formation makes it fitting that this unique piece is given the name ‘buffalo’. This is a true masterpiece carved by nature’s hand.”
Kagem has a history of extraordinary discoveries, including Insofu (6,225 carats, 2010), Inkalamu (5,655 carats, 2018), and Chipembele (7,525 carats, 2021). The tradition of naming only the rarest uncut emeralds links each discovery to Zambia’s rich wildlife heritage. The buffalo was chosen to symbolise determination, endurance, community spirit, and immense strength.
Geologist Dharanidhar Seth and chiseller Justin Banda were credited with the delicate extraction of Imboo. “Even under a strong light, the gem reveals an intense verdant green touched with golden warmth and a clarity that captivates the eye,” explained Adrian Banks, Gemfields’ Managing Director – Product and Sales.
He added that the stone could yield several fine-quality cut emeralds, potentially forming a complete high jewellery suite.
The gem will also benefit from nanoparticle tagging by Provenance Proof, ensuring traceability from mine to market. This guarantees transparency for future owners, preserving its historical significance.
Geologists attribute Imboo’s formation to the “Tri-Junction Model,” a geological phenomenon where three lithological and structural domains converge, providing ideal conditions for the creation of large emerald crystals.
Hemant Azad, Head of Geology at Kagem, described the discovery as “an ancient masterpiece revealed in our modern age,” while Senior Manager for Geology, Debapriya Rakshit, emphasised that each emerald is “a geological time capsule, brought to light after over 500 million years in darkness.”
Kagem’s careful, hand-based recovery methods not only preserve the stone’s integrity but also minimise environmental impact, underlining the mine’s reputation as a responsible global leader in coloured gemstones.
With Imboo, Zambia’s status as home to the world’s finest emeralds is further cemented – a legacy of natural beauty that continues to shine on the global stage.
