KMF Rocks Tsumeb - History
The fascinating history of Tsumeb - One of the worlds most famous mines.

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The History of Tsumeb

The name Tsumeb, according to Mrs. I. Schatz the curator of Tsumeb Museum, may have been derived from "Tsombtsou" from the Bushman language meaning "to dig a hole which collapses again". This was told to her from a Bushman witch doctor that explained that his forefathers had tried to dig a well in the karst rock near the "green hill" which kept collapsing. It must be assumed that due to the high metal content of the 'green hill' little to no vegetation could have survived such a toxic environment and so it would have been quite prominent. It is not known when mining commenced at Tsumeb but the green colored hill must have attracted attention of man from early times. The Bushmen who lived at Otjikoto Lake some 24km away were attracted to it and mined mainly the malachite from the hill of secondary copper minerals, which was approximately 180m long by 40m wide and up to 12m high. The ore was then traded with the Ovambos, a local tribe, who had the knowledge of smelting. The Ovambos made termite hills into a furnaces using charcoal to reduce the ore and utilizing bellows of goats-skin to force air into this primitive smelter. A hole made into the furnace allowed the metal to flow out forming a copper rod. These copper rods were then fashioned into jewelry or tools and later bartered. This complementary trading with the Bushmen continued for some time until the Ovambos went in search of the source of the raw material of their copper metal but were attacked by the Bushmen who wished to keep their secret. Tsumeb was not the only copper deposit in the Otavi Mountain Region and soon the Ovambos controlled other sites. The earliest account of mineral deposits comes from the diary of Sir Francis Galton in 1851 when he met both Bushmen and Ovambos transporting copper near the Otjikoto Lake. Later in 1857 Rhenish missionaries in 1857 noticed this trade also when in the Otavi Region. Two Americans visiting the area in 1875 noticed the copper ore near Otavi and sent samples for analysis to Cape Town which gave positive results and they were advised to start digging the ore. The Ovambos however, who guarded their deposits jealously, began to take a hostile attitude and the two men had to leave. Thus the knowledge that copper deposits occurred in the Otavi Mountain Region became known to the outside world and began to stimulate interest but the deposit at Tsumeb was still a secret. In 1893, Matthew Rogers on an expedition sent from London to Otavi Lands arrived at the Green Hill at Tsumeb and stayed for approximately one year. It was Rogers who made the first assessment of the potential of the Tsumeb deposit. During this period he sank two shafts with crosscuts, each of 20m deep and concluded that it was the best example of a mineral deposit he had seen as assays of the ore gave values of c.10% copper and c.43% lead with credits of silver and gold. Rogers' assessment would prove to be most accurate, as later Tsumeb was to be one of the richest mines in the World. In February 1893, the South West Africa Company sent out a representative, Dr. G. Hartman. The preliminary exploration of the Otavi mineral deposits consumed much capital of the South West Africa Company and a new company to explore and exploit the mineral deposits was initiated with the help of German banking Groups. This new company was named Otavi Minen-und Eisenbahn-Gesellshaft (OMEG) and was founded on 6th April 1900. A second expedition, now sent by OMEG led by Christopher James, arrived at Tsumeb on the 13th August 1900 to evaluate the potential of the Tsumeb deposit. By March the 14th 1901 he had sunk 38m of shaft and had started crosscutting. These crosscuts, some of 18m and 48m respectively, outlined the extent of the Tsumeb ore pipe and by 13th August 1901 he was in a position to give his preliminary report. This report stated that there were over 200,000 tones of high grade ore between surface and 2 Level grading 12.61% copper and 25.29% lead, and over 190,000 tones of low grade at 2.91% copper and 4.3% lead, he had also identified that the western end was copper rich and the eastern lead rich. He estimated a mine life of just over eight years, however this turned out to be just over eighty! In his report he comments on the mineralogy of ore in which he observed chalcocite, malachite, galena, and cerussite, this was the first description of minerals in the Tsumeb deposit. In order to exploit the orebody he recommended the building of a railway from the coast to transport material in and concentrates and metal out. On the basis of the evaluation by James, OMEG increased its share capital and in 1903 the Colonial Company obtained the mining rights to a large area around the Otavi Mountains, which included Tsumeb, and OMEG agreed to construct a railroad. By 1905 work had commenced at Tsumeb to rehabilitate the shafts and crosscuts excavated by James in preparation for mining after the transfer of the Engineer-in-Charge, Mr Gathmann to the mine site. By 1906 the railroad from the coast at Walvis Bay to Tsumeb was completed and a new two-compartment shaft was being sunk. By this time the dumps were being hand sorted, an incline haulage was being constructed for the open pit, development was underway on 2 and 3 Levels, and just being started on 4 Level. From the beginning it was realized that a substantial part of the ore was not of a sufficiently high grade for export. Early in 1907 a therefore a smelter was erected to smelt both the high grade copper and lead ores. Prior to 1908 the only method of ore concentration was by hand sorting but in that year a concentration plan was built. The first full fiscal year of production from April 1907 to March 1908 showed extremely satisfactory results. In the mine the first important flow of water was struck in a winze below 3 Level and carbon-dioxide gas encountered east of the main shaft. Some fifteen months later more water was struck in another winze between 3 and 4 Levels and larger capacity pumps had to be installed. The mining method employed at that time was by cutting sub-levels at a 7m vertical spacing below 1Level; drives and crosscuts were 4m high leaving a horizontal crown resting on pillars so neither timber or fill was used as support. The Crown pillar would eventually be removed by opencast mining operations. On the eastern side of the orebody a cut-and-fill method was used on an advancing 2m high brow, extending the whole width of the orebody. After a fall of the hanging wall and a fatality, a system of narrow transverse stopes, which were backfilled, was introduced. At first all mining was done by hand drilling and by candle light with up to 20 crews employed but by 1909 jackhammers were taken into service. A hand-operated diamond drill employed in the same year started exploring the orebody. After a slow and unsuccessful start it proved its worth by proving up further reserves to 24m below 4 Level by 1911. Export ore from the eastern side of the orebody at that time averaged over 16% copper while smelting ore was derived from the western end. During this time a new inclined hoist was being built on the side of the open pit to remove ore down to 2 Level. As from August of that year the east and west open pits were joined to form one pit as the intervening low grade ore was too badly fractured and unsafe to leave in place. Just prior to World War I the ore reserve increased and additional plant and equipment was installed. During hostilities during the war production was brought to a virtual standstill. Even in 1919 candles and oil lamps were still in use but an order had been places for 500 carbide lamps. During the year from 1919 to 1920 over 250,000 tones of ore were hoisted. A fire underground on 1 and 2 Levels during the same year, which lasted almost a month, caused considerable concern and slags were formed locally as a result of the heat. A new shaft now called No.1 Shaft was collared in 1922 that reached 8 Level at the beginning of 1925 and hoisting began in the same year. By 1926 winzes were sunk to explore from 8 Level to 10 Level and from 12 Level to 16 Level as the ore pipe had constricted at that elevation. No.1 shaft was deepened at the same time to 16 Level with development on 11 and 12 Levels. By 1930 reserves had been established on 17, 18 and 19 Levels and output that year was over 200,000 tones of ore. In 1931 the World depression with low metal prices meant that mining was now confined to the upper levels to save costs. By 1932 mining ceased and was on care and maintenance only. A gradual improvement in copper prices after 1937 led to a gradual recovery with mining recommencing and by 1938 was in full swing again with development on 20 Level. Mining ceased in 1940 just after the outbreak of the Second World War and the Town was under military occupation to 1944. During the period of OMEG control the mine had produced over 200,000 tones of copper, 450,000 tones of lead and 200,000 tones of zinc. During the War years Tsumeb received few visitors and it was not until 1946 a consulting geologist with other staff from O'okeip Copper Company visited the mine. During their visit they made a meticulous examination of the mine records and sampled the dumps. The result of this appraisal gave O'okeip Copper Company, on behalf of Tsumeb Mining Corporation (TCL), the information they required to make a bid for the mine. This was successful and was accepted on January 6th 1947. Mining engineers and other technical staff soon arrived at Tsumeb and with the help of OMEG skeleton staff soon recruited local labor for the reactivation of the mine. At first the dumps were hand sorted and the first trainload of hand-picked high-grade ore sent out by train for export at Walvis Bay by the 17th March 1947 to take advantage of high metal prices. Construction and re-equipping the mine coupled with dewatering began soon afterwards. At the take over by TCl in 1947 the mine was 576m below the surface and most of the ore down to 12 Level had been removed with half the ore mined out below that to 16 Level and development for mining between 16 and 20 Level. By June 1949 the mine had produced over 100,000 tones of ore and geological investigations had proved up five times the reserves of mine-able ore some two years earlier. Evidence soon emerged that the orebody widened considerably with depth as the largest mineralized area found to date was encountered by drilling. One diamond drill hole proved continuity of the ore down to 1027m below surface, with an average grade over 356m of 7.5%Cu, 15.3% Pb, 2.4% Zn. This necessitated the sinking of a new shaft, De Wet, in 1949 from surface to 30 Level with a hoisting capacity of 2000 tones per day, this was completed by 1953. Later drilling at depth to control water encountered another lens of ore from 29 Level down which had a grade of 23% copper. Massive ore at the west-end of the pipe produced a million tones at 3.6% Cu, 26.7% Pb and 12.4% Zn. From 1957 to 1958 a drop in metal prices slowed mining activity, but planning went ahead to mine below 30 Level where drill holes indicated ore continuing for a further 152m. A new internal shaft, No.6 shaft was sunk to 1306m below surface by 1962 and connected to De Wet Shaft and afterwards production started from this depth. From the take over from OMEG the mine had produced over 9 millions tones of ore yet by 1966 the reserves still stood at over 8 million tones. In 1988 there was a change in ownership when the Gold Fields Group of South Africa took over from Tsumeb Corporation. By 1990, the annual mine production of over 600,000 tones of ore had produced over 13,000 tones of blister copper and 9,000 tones of lead with the ore reserves standing at 1.5 million tones. In May 1996 mining ceased on the 48 Level at 1650m below surface due to insufficient ore and high water inflow, which increased pumping costs. In June 1996, the De Wet Shaft was flooded when the pumps were switched off and 700 cubic meters an hour flooded into the mine. Mining on the upper levels continued however, extracting remnants around the stopped out core of the orebody previously mined out by OMEG. The miner's strike, lasting between July and August 1996, stopped mining operations and the mine finally closed and went into liquidation. Mining operations had not resumed until Tsumeb Specimen Mining (Pty) Ltd. recommenced in the Upper Levels on October 2nd. 2000 to prepare to mine for specimens.   Sources of information Gebhard, G.1999. Tsumeb. Pub. G.G. Publishing, Grossenseifen, Germany Sohnge, G.1976. Tsumeb a historical Sketch. Pub. The Committee of the SW Scientific Society, Windhoek. p.92. * Another article we have is  The Geology of Tsumeb *

Minerals A-E

Minerals F-J

Minerals K-O

Minerals P-T

Minerals U-Z