A colossal emerald weighing 11,685 carats—equivalent to 2.3 kilograms—has been unearthed by Gemfields  at the Kagem mine in Zambia, setting a new benchmark in the world of coloured gemstones. By Named Imboo, after the buffalo in the Bemba and Lamba languages, the striking crystal surpasses Kagem’s previous giant, the 7,525-carat Chipembele (“rhino”), which earned Guinness World Records recognition in 2022.

While an emerald claimed to be even larger—53,750 carats—was exhibited in January 2025 by Almighty Gems in Coimbatore, India, that stone has not yet undergone independent authentication. By contrast, Gemfields’ Imboo discovery has already drawn global attention and will headline the company’s ongoing auction in Bangkok, running through 11 September.

The massive crystal was extracted on 3 August from the mine’s Chama pit by geologist Dharanidhar Seth and long-time chiseller Justin Banda. Gemfields said the buyer will be offered Provenance Proof nanoparticle tagging, ensuring full traceability even after cutting and polishing.