Karl (sometimes Carl) Schmeisser, a German mining expert, was the son of Christian Schmeisser, a medical practitioner, and his wife Marrianne Dresler. Karl studied geology and mining at the Bergakademie (Mining Academy) in Berlin and during his student days visited various mining regions in Germany. After graduating in mining in 1879 he continued to expand his knowledge by studying mines in Germany, Belgium and northern France. He was employed by the railway administration in western Germany for five years before joining the Prussian Department of Mines, where he was promoted to Bergrat (Mining Commissioner) in 1890 and became an expert in the mining of precious metals.
In 1893 the Prussian government sent him to the South African Republic (Transvaal) to evaluate the extent and future prospects of its gold mining industry and its potential as a market for German industry. During a stay of four months he visited Kimberley, the Witwatersrand, Klerksdorp and the neighbourhood of Vredefort; the gold-fields of Pietersburg (now Polokwane), Leydsdorp, Lydenburg, Pilgrim's Rest and De Kaap; and the coal-fields at Middelburg. As a basis for his geological description of the country he used the stratigraphy proposed by Dr Adolf Schenck*, which later proved to be much oversimplified. The gold reefs at Klerksdorp convinced him of the great westward extension of the gold-bearing conglomerates of the Witwatersrand. He noted that his collection of fossil plants from the Transvaal coal-fields contained an abundance of Glossopteris plants and hence was able to show that these coal-fields belonged to the Ecca Group and could not be correlated with the Stormberg coal-fields of the Cape Colony as had generally been assumed. This discovery furthermore proved that the breccia which had been metioned by A.R. Sawyer* and others as underlying the Transvaal coal-fields corresponded to the Dwyka tillite of the Cape Colony, which was an important stratigraphical advance. Later work confirmed these conclusions.
Schmeisser's findings were set out in a report, "Bericht über die Nachhaltigheid des Goldbergbaus in der südafrikanischen Republik Transvaal" (Report on the durability of gold mining in the South African Republic Transvaal), published in the Deutsche Reichsanzeiger (Government Gazette) in 1894. A more comprehensive publication soon followed, entitled Ueber Vorkommen und Gewinnung der nutzbaren Mineralien in der südafrikanischen Republik (Transvaal) unter besonderer Berücksichtigung des Goldbergbaues (On the presence and recovery of useful minerals in the South African Republic, with special consideration to gold mining; Berlin, 1894, 151p). This work remained an excellent reference work on the mineral industry of the Transvaal for many years. It included petrographical desriptions of many rocks by Dr A. Koch. Two other publications resulting from his visit were papers on "Der Goldbergbau in der südafrikanischen Republik Transvaal und seine Bedeuting für die deutsche maschinenindustrie" (Gold mining in the South African Republic Transvaal and its significance for the German machine industry, 1894), and "Geographische, wirtschaftliche und volksgeschichtliche Verhältnisse der S.A.R., sowie deren Beziehungen zu England" (Geographical, economic and national-historical relations in the S.A.R., as well as its relations with England, 1900). He was elected an honorary member of the Geological Society of South Africa.
Schmeisser's reports were of great importance for the development of the gold mining industry. His main conclusion was that the gold mines of the Transvaal would probably be able to produce gold to the value of £349 000 000 over the next 40 years. This helped to create a world-wide boom in South African gold shares and supported the views of German financiers that their currency should be backed up by gold reserves. German exports of mining machinery, railway material, chemicals, cement and other products to the South African Republic increased considerably.
Schmeisser's expertise was recognised also outside Germany and in 1895 he was contracted by British organisations to investigate gold-fields in Australia, Tasmania and New Zealand. Returning to Europe via North America he visited gold, silver and iron ore mines in California, Nevada and Colorado. The results of this expedition were published in two papers (1896) and in Die Goldfelder Australasiens (Berlin, 1897), translated as The gold-fields of Australasia (London, 1898). A few years later, recognised as a leading scientist and outstanding organiser, he was appointed director of both the Prseussische Geologische Landesanstalt (Prussion Geological Survey) and the Bergakademie in Berlin. He published Die geschichte der geologie und das montanwesens in den 200 jahren des preussischen königreichs... (The history of geology and mining during the 200 years of the Prussian kingdom..., Berlin, 1901), as well as several papers on the mineral resources and the development of mining in the German colonies between 1902 and 1908. During the latter part of his career he received numerous decorations and honorary titles.