Kagem Emerald Mine, Zambia

Kagem Emerald Mine

About Kagem

Let us introduce you to Kagem, believed to be the world’s single largest emerald producing mine.

Located in the southern part of Zambia’s copper belt, this open-pit mine lies in the centre of a mineral-rich province called the Ndola Rural Emerald Restricted Area.

Following the liberalisation of mining in the early 1990s, Zambia has become one of the most valuable emerald sources in the world.

Since acquiring the Kagem mine in 2008, in partnership with the Government of the Republic of Zambia through the Industrial Development Corporation (IDC), Gemfields’ investment has stabilised and standardised the supply of emeralds, transforming the operation and the communities that surround it.

Emerald Mining at Kagem

Zambian emeralds are among the oldest on earth – created by contact between beryllium, chromium and vanadium more than 500 million years ago.

Chromium and vanadium are what give emeralds their beautiful green hue. These precious gemstones are said to symbolise growth, new beginnings and fertility.

When an emerald is recovered at Kagem, it is the first time that light has ever passed through the crystal, bringing it to life after half a billion years in darkness.

Kagem’s emeralds are found underground in hard rock. The dedicated team methodically search areas that display the characteristics necessary for emerald formation: where bands of pegmatite and high-grade metamorphic rock meet. They are experts at recovering emeralds by hand, enabling the safe recovery of some of the largest and most exceptional emeralds ever found, including the 5655 carat ‘Lion Emerald’ Inkalamu.

After waste rock has been removed, displaced topsoil is saved to create seedbanks, which is then used to grow indigenous plants and replant trees. When the emerald mining process is complete, the natural environment is restored.

Recovered emeralds are transferred to the sorting house, where they are cobbed by hand – small pieces of hard rock are carefully removed from emerald crystals. Lower-quality emerald-bearing rock is checked for crystallisation along picking lines and cobbed mechanically. The emeralds are sorted and graded according to their colour, size, shape and clarity.

The emeralds then head off for sale at auction, typically in Lusaka or Singapore. The proceeds are fully repatriated to Zambia and all royalties due to the government are paid on the full sales price.

After auction, the rough Zambian emeralds enter the international markets to be traded as rough, or cut and polished by skilled hands (usually in Jaipur), before being sold to jewellery houses, designers, collectors or gemstone traders.

How Emeralds Are Formed

Emeralds can only form when two different rock types with contrasting characteristics meet each other under unique geological conditions, making it one of the rarest gemstones in the world.

For Zambian emeralds – which are among the oldest on earth – this was the combination of the circa 1.6 billion-year-old high-grade metamorphic rock named the Talc Magnetite Schist (TMS) and the younger circa 500-million-year-old intruding pegmatite.