Kagem Emerald Mine, Kafubu emerald mining district, Lufwanyama District, Copperbelt Province, Zambiai

Regional Level Types
Kagem Emerald Mine	Mine
Kafubu emerald mining district	Mining District
Lufwanyama District	District
Copperbelt Province	Province
Zambia	Country

Company founded in 1984 to regain control of mines in the Kafubu district.
Apparently "Africa's largest emerald mine" (Elements 5 (2009) p. 157). 15-20% of the emerald world production comes out of this mine (Behling, 2009).

The mine covers an area of 1 square km.
Emerald crystals of very high quality are extracted from quartz lenses.

In 2022, the Kagem Mine produced a total of 37.2 million carats of emeralds and beryl, including 259,500 carats of premium emeralds.
The emeralds ranged from green to blueish green, and some displayed an attractive saturated bluish-green color. The refractive indices varied from 1.578–1.591 for ne and 1.589–1.597 for no with birefringence between 0.004 and 0.008. These values are higher than most of the significant emerald deposits. Specific gravity values ranged from 2.67 to 2.86. The emeralds from the Kagem Mine were typically inert to long- and short-wave UV radiation. The emeralds showed no reaction under the Chelsea filter. Dichroism was medium to strong yellowish green (o-ray) and bluish green (e-ray).
The Kagem emerald concession covers an area of approximately 46 square kilometers within a 200-square-kilometer productive zone and comprises the current operating Chama open pit mine and the bulk sampling pits at Libwente and Fibolelem.
The emerald mineralization in the Kagem Mine results from the interaction between metabasites and pegmatites and their accompanying hydrothermal fluids. Emeralds are found in the phlogopite reaction zone (typically 0.5–3 m wide) between the talc-magnetite schist and the pegmatites and in the quartz-tourmaline veins, which produces gem-quantity emeralds, but only a tiny percentage. In the reaction zone, talc-magnetite schist provided the important chromophore of chromium, while the pegmatites provided the beryllium. Emerald was formed under the proper pressure, temperature conditions (400–600 MPa and 590–630 °C) and chemical environment around 500 Ma. The area subsequently underwent intense shearing and folding during the Lufilian orogeny, which may account for the fracturing and opacity of many emerald crystals.

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