Zambia has unveiled an extraordinary 11,685-carat emerald, the largest gem ever unearthed at Kagem Mining, a company spokesperson confirmed. Named Imboo, or “buffalo,” the gemstone surpasses previous Kagem discoveries, cementing the mine’s reputation as the world’s top emerald producer.
Geologist Dharanidhar Seth and veteran chiseller Justin Banda discovered Imboo on August 3, 2025, at the Chama pit, the company said. Kagem’s history of giant finds includes the 6,225-carat Insofu in 2010, the 5,655-carat Inkalamu in 2018, and 7,525-carat Chipembele in 2021.
Weighing 2.337 kilograms, Imboo stands out not only for size but also for its exceptional clarity and deep emerald hue. Gemfields plans to showcase Imboo at its high-quality emerald auction in Bangkok, Thailand, running from August 25 to September 11, 2025.
All proceeds from the auction will be repatriated to Zambia, reflecting the country’s growing role in global gemstone trade. The discovery reinforces Kagem Mining’s position as a source of world-class emeralds, drawing attention from collectors and investors alike.
Imboo’s monumental size and quality mark it as one of the most remarkable gemstones ever recovered in modern mining history. Gemfields celebrated the find as a testament to skilled mining techniques and decades of local expertise at Zambia’s leading emerald mine.