Tanganyika Concessions Limited[a] (TCL or Tanks) was a British mining and railway company founded by the Scottish engineer and entrepreneur Robert Williams in 1899.

Partly-owned subsidiaries included the Union Minière du Haut-Katanga (UMHK), which undertook mining in the Katanga portion of the copperbelt, and the Benguela railway, which provided a rail link across Angola to the Atlantic Ocean.

[4] It covered more than 2,000 square miles (5,200 km2) north of the Zambezi river with exclusive rights for prospecting and locating 1,000 claims.

[11] About´10 miles (16 km) south of the border they found the workings of the ancient Kansanshi copper mine, and on 6 September 1899 staked claims there for TCL.

Williams tried unsuccessfully to interest King Leopold II of Belgium in full-scale exploitation of the copper belt.

Leopold was starting to earn high returns from rubber and ivory exports, and resented British criticism of his brutal treatment of the local people, so held back.

[8] In early 1903 Williams discussed building a railway from Lobito on the Atlantic coast of Angola to the copper mines with the contractors Pauling & Co., but the costs proved excessive.

[14] Instead, the Rhodesian railway was extended north from Bulawayo via the Wankie (Hwange) coal fields and Victoria Falls, reaching Kalomo in 1905 and Broken Hill (Kabwe) in 1906.

[15] The TCL concession in Katanga expired on 28 October 1906 and the Union Minière du Haut-Katanga (UMHK) was formed to exploit the deposits.

[8] The Société Générale de Belgique and the associated Banque d'Outremer purchased a minority share in TCL in 1923.

[1] In 1981 Société Générale de Belgique acquired a controlling interest in TCL, which still owned 90% of the Benguela Railway.

[24] In 1960, just before independence of the Democratic Republic of the Congo and the dissolution of the CSK, ownership was:[25] In December 1966 President Mobutu Sese Seko announced that a new company (later named Société Génerale Congolaise de Minerais (Gécamines) would take over from UMHK as of 2 January 1967.

It ran from Lobito to Texeira de Sousa (Luau), then crossed the Luao River into the Belgian Congo at Dilolo.

[30] During the subsequent Angolan Civil War (1975–2002) the railway remained closed and the tracks, bridges and rolling stock were destroyed.

[31] TCL made an agreement in 1908 with the government of the Belgian Congo to build a railway from Broken Hill to the Katanga Border.

The Rhodesia-Katanga Junction Railway & Mineral Company was formed for this purpose, and also took over the Kansanshi mine and TCL's other copperbelt holdings.

[36] A 1937 report said it hoped to soon start crushing 500 tons per day, and could well become the largest gold producer in East Africa.

It had built housing, medical facilities, set up a private wireless station and subsidized a weekly air service.

[33] In the early 1950s Geita employed about 2,000 men and produced more than half of the gold mined in Tanganyika, although this was much less than the peak production before World War II (1939–1945).

[39] The syndicate explored the Hofrat en Nafas Copper Mine in southern Darfur between 1918 and 1922, sinking shafts and boreholes, but eventually abandoned the effort.

[42] In 1895 it was reported that the Zambasia Exploring Company had placed a large number of shares in United Rhodesia Goldfields in Paris.