Kansanshi History (First Quantum) - Zambian Copperbelt (sitios de interés)

History:

 

The Kansanshi deposit is the site of one of the oldest known mines in Zambia, with evidence of direct copper smelting dating back to the fourth century. Since the rediscovery of these ancient workings in 1899, the deposit has been mined intermittently for recovery of high grade copper ore.From 1903 until 1914, copper was recovered by underground mining of high-grade veins, followed by hand sorting and direct smelting. Mining activities terminated with the onset of World War I, resumed in 1927, but were shut down again in 1932 due to the world wide economic depression.

In 1952, further exploration and mine development commenced, with production resuming in 1956. Rich oxide ore from the upper levels of the underground mine was shipped to Nkana on the Copperbelt for direct smelting. Sulphide concentrates were also produced on site from rich vein ore from lower mine levels through a small concentrator. The concentrates were shipped to the Nkana smelter for processing until October 1957.

 

In 1969, Zambia Consolidated Copper Mines (ZCCM) approved development of an open pit mine at Kansanshi to treat high grade oxide ore in a leach plant to be constructed at the Kansanshi site. Construction commenced in 1974 with the building of houses and an office block but the project was shelved at the end of 1975 due to low copper prices. In June 1977, a “mining only” option was initiated at Kansanshi to deliver oxide ore to the Copperbelt for treatment and copper recovery at the Nchanga leach plant. This activity continued through April 1986 when operations ceased for economic reasons. During 1988,ZCCM constructed a small sulphide flotation concentrator at site with a capacity of approximately 200 t/d and recommenced open pit mining activities. Concentrate from the facility, containing up to 15 g/t Au, was transported to the Copperbelt for smelting. This operation continued until January 1998, at which time ZCCM formally ceased operations and initiated closure and reclamation activities. Total production of copper from the Kansanshi deposit to date has been approximately 80, 000 t.

In January 1997, as a part of a privatisation programme, Cyprus Amax Minerals Company (Cyprus) entered into an agreement with ZCCM and the Government of the Republic of Zambia to secure majority ownership of surface leases and selected assets associated with the Kansanshi project. Cyprus initiated geological investigations and
metallurgical testwork in May 1997, aimed at developing reserves capable of supporting a major copper mining facility. Cyprus became a part of Phelps Dodge during the undertaking of a Preliminary Feasibility Study (PFS). This PFS examined Cu production of 124 000 t/a over a 24 year life, from mining of a total of 267 Mt of ore. This comprised 101 Mt of Mixed ores requiring flotation and leaching, together with 166 Mt of Sulphide ores requiring only flotation. Following submission of the PFS, Phelps Dodge determined that the Kansanshi Project did not meet its corporate requirements and tendered the Project for sale.

 

FQM acquired majority ownership and management control of the Project, reviewed a number of options and determined that a progressive development plan, initially focussing on near surface, higher grade, leachable ores, was more appropriate. Phase 1 of the development plan, which is the focus of the DFS, visualises production of 60 000 t of cathode copper per annum, plus variable amounts of copper in flotation concentrates, while minimising capital investment. Future plant upgrades would entail staged expansion of the throughput capacity to allow treatment of lower grade Sulphide ores and, ultimately, installation of facilities for on-site treatment of sulphide concentrates.

 

Kansanshi Mining Plc
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