Gemfields has unveiled Imboo, an 11,685-carat emerald discovered at its Kagem mine in Zambia, the largest exceptional gemstone ever recovered at the site. The stone is being offered at the company’s latest high-quality emerald auction, running from 25 August to 11 September 2025 in Bangkok.
Weighing 2,337 grams, Imboo displays a vivid green hue with golden undertones. “Even under the beam of a strong light that is necessary to illuminate a gemstone of this remarkable size, Imboo 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.
“It is easy to imagine Imboo giving rise to several fine-quality cut emeralds of significant size. Such a rare collection could form an entire high jewellery suite from this single gemstone. This remarkable find may tempt its new owner to see it not only as a source of extraordinary gems, but as a unique investment destined to be remembered in the annals of exceptional emeralds,” he added.
Discovered on 3 August in Kagem’s Chama pit, the emerald continues the mine’s tradition of naming rare finds after African wildlife, following Insofu (elephant, 2010), Inkalamu (lion, 2018) and Chipembele (rhino, 2021).
Gemfields said the buyer will be offered Provenance Proof nanoparticle tagging, ensuring full traceability even after cutting and polishing.
“In my thirty years at Kagem, I’ve rarely seen such a remarkable formation of large, high-quality crystals,” commented Jackson Mtonga, Grading Manager – Sort House, Kagem. “The immense size and nature of the crystal formation makes it fitting that this unique piece is given the name ‘buffalo’, or Imboo in our local languages. This is a true masterpiece carved by nature’s hand,” he concluded.