Historical Reading List: Alluvial Diamonds from Namibia
A little more than a century ago in May 1908, loose alluvial diamonds were first found in beach sediments near the small town of Lüderitzbucht in the former German colony of Southwest Africa (now Namibia). Over the next few years, rich diamond deposits were found along a narrow region of the Atlantic coastline southward from Lüderitz Bay to the Orange River at Oranjemund. The diamonds could be recovered from ancient beach terraces that now lie inland, on the modern beaches, or from the ocean bottom along the shore. A land rush to this barren desert region ensued, and within six months of the discovery, the German government created a restricted diamond mining area known as the Sperrgebiet (or restricted area) that extended 100 kilometers inland and 320 kilometers along the coast. Most mining rights within the area to control the recovery and sale of diamonds were initially granted to the Deutsche Diamantengesellschaft (the German Diamond Corporation). After Germany’s defeat in World War I, South Africa took over the administration of the colony, and the diamond mining area came under eventually control of De Beers which managed it until the 1990s. At that time, the Namibian government entered into a joint venture relationship with De Beers to recover and market the diamonds. Diamonds are recovered beneath beach sands along the coast, as well as from sediments dredged up by special ships from the seafloor.
These alluvial diamonds are thought to have originated from primary kimberlite pipes within the high central plateau in the interior of South Africa (more than 300 miles to the east). Over some 80 million years of geologic time, the diamonds were transported down to the Atlantic Ocean by the Orange and other river systems, and then carried northward along the coast by ocean currents to be deposited either on the shallow ocean bottom or along the coastline. This extended distance of water transport tended to winnow out poorer-quality crystals, so the vast majority of the diamonds found in this remote coastal area are suitable for gem use.
How To Use This Reading List
This reading list was compiled to give you an opportunity to learn more about the history of alluvial diamonds from Namibia. A number of the articles were published in the 1800s and early 1900s – when many classical gem deposits of historical importance were discovered – and gemology and mineralogy became sciences. The list is presented in chronological order to emphasize the development of ideas over time. The list is not comprehensive, but a compilation of the some interesting gemological information that has often been forgotten or overlooked.
Many of the articles exist in the public domain and can be found online at digital libraries such as Hathitrust, Internet Archive, or other digital repositories. More recent publications can often be found in libraries, including the Richard T. Liddicoat Gemological Library. Abstracts of these articles can usually be found on the website of the original journal or magazine, and the article itself is often available for purchase from the publisher.
Regarding the GIA library’s holdings and on-site access, please contact the GIA library in Carlsbad.
Kommen in Deutsch-Südwestafrika Diamanten vor? [Do Diamonds Occur in German Southwest Africa?], H. Mentzel, Glückauf: Berg- und Hüttenmännische Wochenschrift, Vol. 39, No. 24, pp. 553-555, (1903). Based on the diamond discoveries in South Africa, the author speculates on the possible occurrence of diamond-bearing kimberlites in the country.
Welche Aussichten eroffnet die Neuere Entwicklung des Diamantbergbaues im britischen Südafrika fur das Aufkommen einer Diamantgewinnung in Deutsche-Südwestafrika? [What Prospects have opened up by the new Development of Diamond Mines in British South Africa for the Advent of Diamond Mining in German Southwest Africa?], A. Macco, Deutsche Kolonialzeitung, Vol. 24, No. 28, pp. 280-282, (1907). The author discusses the competition to diamond mining in the German colony by the recent development of mines in South Africa.
Diamantgewinnung in Deutsch-Südwestafrika [Recovering Diamonds in German Southwest Africa], K. Weegmann, Deutsche Kolonialzeitung, Vol. 24, No. 33, pp. 333-334, (1907). This is a brief report on finding diamonds.
Zu den Diamantfunden in Deutsch-Südwestafrika [To the Diamond Find in German Southwest Africa], G. Gürich, Die Umschau, Vol. 12, No. 45, pp. 889-892, (1908). This is one of the first detailed reports of the discovery of diamonds along the coastline in Namibia.
Die Diamantfunde von Lüderitzbucht [The Diamond Discovery at Lüderitz Bay], Unknown author, Deutsche Kolonialzeitung, Vol. 25, No. 34, p. 597, (1908); and Die Diamanten von Lüderitzbucht [The Diamonds of Lüderitz Bay], Unknown author, Deutsche Kolonialzeitung, Vol. 25, No. 40, pp. 709-710, (1908). Short descriptions of the alluvial diamond discovery near Lüderitz Bay.
Die Diamantvorkommen in Deutsch-Südwestafrika und ihre Bedeutung für das Schutzgebiet [The Diamond Occurrence in German Southwest Africa and its Importance for the Restricted Zone], O. Gallus, Zeitschrift für Kolonialpolitik, Kolonialrecht, und Kolonialwirtschaft, Vol. 11, pp. 944-960, (1909) and Vol. 12, pp. 29-58, (1910). A report on the effect of diamond mining on the economy of the German colony.
Die Diamantvorkommen in Lüderitzland, Deutsch-Südwestafrika [The Diamond Occurrence in the Lüderitz Country, German Southwest Africa], H. Merensky, Zeitschrift für Praktische Geologie, Vol. 17, No. 3, pp. 122-129, (1909). The author describes the discovery of the first diamonds near Lüderitz. Based on the limited economic success of working alluvial diamond deposits found previously elsewhere, at first there was limited interest concerning the new discovery. However, when verified reports soon arrived of a daily production of 5000 carats, the potential importance of these deposits was recognized. An English version of this article appeared in the Transactions of the Geological Society of South Africa, Vol. 12, pp. 13-23, (1909).
Die Nutzbaren Lagerstätten von Deutsch-Südwestafrika [The Usable Ore Deposits of German Southwest Africa], C. Gagel, Zeitschrift für das Berg-, Hütten- und Salinen-Wesen im Preussischen Staate, Vol. 57, pp. 173-184, (1909). A review is presented of the economic ore deposits in the German colony, including the deposits of alluvial diamonds.
Über die Diamantablagerungen bei Lüderitzbucht [On the Diamond Deposits of Lüderitz Bay], H. Lotz, Zeitschrift der Deutschen Geologischen Gesellschaft, Vol. 61, (March), pp. 135-146, (1909); and Die Diamantenfelder bei Lüderitzbucht [The Diamond Fields near Lüderitz Bay], P. Range, Deutsches Kolonialblatt, Vol. 20, No. 22, pp. 1039-1048, (1909). These two articles give detailed descriptions of the diamond deposits near Lüderitz.
Die Diamantfelder bei Lüderitzbucht [The Diamond Fields near Lüderitz Bay], Unknown author, Deutsche Kolonialzeitung, Vol. 26, No. 48, pp. 794-795, (1909). Information provided by P. Range on the diamond production from Lüderitz Bay.
Über die Herkunft der Diamanten von Deutsch-Südwestafrika [On the Origin of the Diamonds in German Southwest Africa], J. Kuntz, Zeitschrift der Deutschen Geologischen Gesellschaft, Vol. 61, (April), pp. 219-221, (1909). The author discusses several possible theories for the source of the diamonds, and he concludes they came down the Orange River from the kimberlite pipes in the central part of southern Africa.
Some Interesting Information as to the New Diamond Fields in German Southwest Africa, Author unknown, Jewelers’ Circular-Weekly, Vol. 58, No. 10, pp. 71 and 73, (1909). A report from the U.S. Consul in Germany on the new diamond deposits.
Diamantengewinnung in Deutsch-Südwestafrika [Recovering Diamonds in German Southwest Africa], C. Gagel, Die Woche, Vol. 11, No. 8, pp. 339-342, (1909). The methods used to recover diamonds from coastal sands are described.
Ueber Diamanten aus Deutsch-Südwestafrika [On the Diamonds of German Southwest Africa], E. Kaiser, Centralblatt für Mineralogie, Geologie und Paläontologie, No. 8, pp. 235-244, (1909); and Das Vorkommen der Diamanten in Deutsch-Südwest-Afrika [The Occurrence of Diamonds in Germany Southwest Africa], Aus der Natur, Vol. 5, No. 11, pp. 328-337, (1910). These two articles by the same author provide a description of the diamond occurrence in the German colony.
Mining Industry of Southwest Africa, T.H. Norton, Mining and Engineering World, Vol. 30, No. 15, p. 672, (1909). A brief report is given on the diamond mining industry.
The Origin of the German South-West Africa Diamonds, P.A. Wagner, Transactions of the Geological Society of South Africa, Vol. 13, pp. 56-60, (1910), and Notes on the German South-West African Diamonds, C. Krause, Transactions of the Geological Society of South Africa, Vol. 13, pp. 61-64, (1910). According to the authors, the increasing production has meant that the origin of the diamonds in Southwest Africa had become an important geological question. Observations on the occurrence of diamonds are presented, including information by German geologists who had visited the deposits.
Notes on the Origin of the Diamonds in German Southwest Africa, R. Marloth, South African Journal of Science, Vol. 6, No. 3, pp. 112-113, (1910). The author briefly reviews previously published articles on the origin of the diamond deposits. A similar article appeared in the Mining and Engineering World, Vol. 32, No. 8, p. 418, (1910).
Zur Südwestafrikanischen Diamantenfrage [The South-West Africa Diamond Question], Unknown author, Deutsche Kolonialzeitung, Vol. 27, No. 16, pp. 255-256, No. 17, pp. 272-273, and No. 18, pp. 287-288, (1910). Discussion of legal questions surrounding the recovery of diamonds along the coast of the colony.
Die Diamanten Deutsch-Südwestafrikas [The German Southwest African Diamonds], P. Prior, Bericht der Senckenbergischen Naturforschenden Gesellschaft in Frankfurt am Main, Vol. 41, pp. 133-141, (1910). The author describes the diamond fields near Lüderitz.
Die Diamantenfelder bei der Conception-Bucht [The Diamond Fields near Conception Bay], F. Voit, Deutsches Kolonialblatt, Vol. 21, No. 8, pp. 326-331, (1910). The alluvial occurrences of diamond around Conception Bay are described.
Zur Geschichte der Südwestafrikanischen Diamantenfunde [The History of the South-West African Diamond Find], G. Badermann, Deutsche Goldschmiede Zeitung, Vol. 13, No. 13, pp. 124-125, No. 15, pp. 140-142, No. 17, pp. 151-157, and No. 19, pp. 178-179, (1910). Historical information on the discovery of diamonds in the German colony is presented.
Die Deutsche Diamantenküste [The German Diamond Coast], H. Grimm, Die Woche, Vol. 12, No. 41, pp. 1752-1755, (1910). The coastal diamond deposits are described.
Die Schätze der Diamantenkolonie [The Wealth of the Diamond Colony], A. Zimmermann, Die Woche, Vol. 12, No. 19, pp. 711-712, (1910). The author discusses the economic importance of the coastal diamond deposits.
Das Vorkommen der Diamanten und des Blueground’s Deutsch-Südwestafrikas in Geologische Hinsicht [The Occurrences of Diamond and Blue Ground in German Southwest Africa in Geological Terms], R. Scheibe, Verhandlungen des Deutschen Kolonialkongresses, D. Reimer Verlag, Berlin, pp. 32-40, (1910). A description is given of the coastal alluvial deposits of diamonds and the occurrences of blue-ground (kimberlite) within the colony.
A New Diamond Field in German South-West Africa, Unknown author, American Review of Reviews, Vol. 44, (September), pp. 368-369, (1911). A brief description of the diamond field.
Die Bergrechtlichen Verhältnisse und die Diamantenfrage in Südwestafrika [The Legal Mining Conditions and the Diamond Questions in South-West Africa], Unknown author, Deutsche Kolonialzeitung, Vol. 28, No. 21, pp. 352-354 and No. 22, pp. 369-372, (1911). A discussion of the legal regulations governing diamond mining along the coast of the colony.
Der Deutsch-Südwestafrikanische Diamantenstreit [The German Southwest Africa Diamond Dispute], A. Arndt, Koloniale Rundschau, No. 1, pp. 5-22, (1911). The author discusses diamond mining along the Namibian coast.
Lüderitzbucht und das Diamantenland [Lüderitz Bay and the Diamond Land], E. Vollbehr, Die Umschau, Vol. 15, No. 40, pp. 826-832, (1911). The methods used to recover diamonds in Lüderitz Bay are described.
Diamonds in German S.W. Africa, G.P. Ashmore, Mining and Engineering World, Vol. 35, No. 11, p. 802, (1911). A brief description of alluvial diamond mining is provided.
Facts about the Diamond Fields of German Southwest Africa, Unknown author, Jewelers’ Circular Weekly, Vol. 64, No. 1, pp. 121, 123, 125, (1912). A description is presented on the recovery of alluvial diamonds in a remote part of the world that was new at the time to the jewelry industry.
Die Deutsch-Südwestafrikanische Diamantenpolotik im Bergleich mit der Englisch-Südafriakischen [The Diamond Politics in German Southwest Africa in Comparison to British South Africa], P. Baer, Zeitschrift für Kolonialpolitik, Kolonialrecht, und Kolonialwirtschaft, Vol. 12, pp. 782-813, (1912). The author compares the importance of diamond mining for the two countries.
Randglossen zur Deutschen Diamantenproduktion [Notes on German Diamond Production]. H. Lotz, Koloniale Rundschau, No. 4, pp. 193-204, (1912). A review of diamond production from the German colony.
The Occurrence of Diamonds in German South-West Africa, G.P. Ashmore, Transactions of the North of England Institute of Mining and Mechanical Engineers, Vol. 61, pp. 112-114, (1913). The author presents a summary of the diamond deposits.
The Diamond Deposits of German South-West Africa, P.A. Wagner, South African Mining Journal, Vol. 24, Part 1, No. 1197, p. 7, No. 1199, p. 40, No. 1200, p. 54, and No. 1201, p. 71, (1914). This information is condensed from the book “The Diamond Fields of South Africa” by the same author.
Der Diamantenabbau in Deutsch Südwestafrika [Diamond Mining in German Southwest Africa], G. Goldberg, Dingler’s Polytechnisches Journal, Vol. 329, No. 34/35, pp. 531-533, (1914). The author discusses the current state of diamond mining in the German colony.
Die Deutschen Diamanten und ihre Gewinnung [The German Diamonds and Their Recovery], F. Knade, 56 pp, (1914). This is a publication about the recovery of diamonds in German South-West Africa.
Was Bedeuten uns die Südwestafrikanischen Diamanten? [What do we Mean by South-West African Diamonds?], F. Kolbe, Das Grössere Deutschland, Vol. 1, No. 3, pp. 74-80, (1914). The author discusses the importance of the diamond deposits for Germany.
Diamond Fields of German South-West Africa, C.W. Boise, Mining Magazine, Vol. 12, No. 6, pp. 329-340, (1915), and South African Mining Journal, Vol. 24, Part 2, No. 1242, p. 468, No. 1243, p. 494, No. 1244, p. i, No. 1245, pp. 532-533, (1915). The diamond fields, which were considered capable of yielding one million carats per year, are described in these two articles by the same author. The colony had been taken over in 1915 by South Africa.
“South-West Africa during the German Occupation 1884-1914”, A.F. Calvert, T.Werner Laurie Ltd., London, 105 pp. (1915). The author describes the region as a German colony, and he discusses the diamond recovery operations.
“South-West Africa”, W. Eveleigh, Chap. 10, pp. 197-221, T. Fisher Unwin Ltd., London, (1915). This book contains a chapter on the diamond deposits and the history of their development.
The Economic Resources of the German Colonies – II: German South-West Africa, Author unknown, Bulletin of the Imperial Institute, Vol. 13, pp. 242-245, (1915), and Economic Resources of the German Colonies in Africa, W.A. Crabtree, Journal of the African Society, Vol. 16, No. 61, pp. 125-128, (1916). Reviews of the economic resources of the German colony including diamonds are summarized in these two articles.
The Geology and Mineral Industry of German South-West Africa, P.A. Wagner, Union of South Africa Geological Survey Memoir, No. 7, 119 pp., (1916). This memoir contains a section on the diamond deposits.
Diamonds in South-West Africa, H.A. Bryden, Chambers’s Journal, Vol. 6, No. 310, pp. 779-781, (1916). General information is presented on the diamond fields.
The Latest Development of Diamond Winning in South-West Africa, Author unknown, South African Mining and Engineering Record, Vol. 28-1, No. 1427, pp. 495-496, (1919). A brief report is given of the introduction of dredging to recover diamonds from the ocean sediments along the coast.
The Diamond Mining Industry of Southwest Africa, C. Pisar, Jewelers’ Circular Weekly, Vol. 80, No. 17, p. 69, (1920). This is a summary of the mining industry by the United States Vice Consul in Cape Town.
Die Aufbereitung der Südwestafrikanischen Diamantkiese [The Processing of the Southwest African Diamond Gravels], G. Glockemeier, Metall und Erz, Vol. 18, No. 20, pp. 507-519, (1921). A discussion of methods used to recover diamonds from sediments along the coast of Namibia.
The Alluvial Diamondiferous Deposits of South and Southwest Africa, F.C. Cornell, Journal of the Royal Society of Arts, Vol. 69, No. 3557, pp. 136-147, (1921). The author, who had spent nearly a decade studying the diamond deposits in both countries, describes the history of diamond mining and how diamonds are recovered along the coast. The article was reprinted in the Chemical News, Vol. 122, No. 3176, pp. 88-90, No. 3177, pp. 100-102, and No. 3178, pp. 113-116, (1921).
The Diamond Fields of Southwest Africa, J.W. Finch, Engineering and Mining Journal, Vol. 113, No. 8, pp. 317-321, (1922). A discussion is given of the principal mining areas and their production of diamonds.
Die Deutsche Diamantenindustrie und ihre Kontingentierung [The German Diamond Industry and its Allocation], A. Hänig, Fortschritte der Naturwissenschaftlichen Forschung, Vol. 11, pp. 61-76, (1922). A review of the German diamond industry, including mining in the colony of Southwest Africa.
Mining in the South-West Protectorate, Unknown author, South African Mining and Engineering Journal, Vol. 33-2, No. 1620, pp. 96-97, (1922). Some general information is presented on the state of the mining of diamonds and other ores.
South-West African Diamonds, Unknown author, South African Mining and Engineering Journal, Vol. 33-2, No. 1634, pp. 525-527, (1923). The history of the development of the diamond fields is summarized.
The South-West African Diamond Industry, Unknown author, South African Mining and Engineering Journal, Vol. 34-1, No. 1645, pp. 63-64, (1923). A brief review is given of the principal companies involved with diamond mining.
Desert Diamonds, Unknown author, South African Mining and Engineering Journal, Vol. 34-1, No. 1648, pp. 164-165, (1923). The mining operations at Lüderitz Bay are discussed.
“Die Diamantenwüste Südwestafrikas” [The Diamond Desert of Southwest Africa], E. Kaiser, D. Reimer Verlag, Berlin, Vols. 1 and 2, 535 pp., (1926). Publication not seen. A review of this book by F. Jaeger appeared in the Geographische Zeitschrift, Vol. 33, No. 6, pp. 321-329, (1927).
Beiträge zur Kenntnis der Diamantlagerstätten an der Oranjemündung in Südwestafrika [Contribution to the Knowledge of the Diamond Deposits along the Mouth of the Orange River, Southwest Africa], G. Knetsch, Geologische Rundschau, Vol. 28, No. 3/4, pp. 188-207, (1937). Article not seen.
The Consolidated Diamond Mines of South-West Africa, Limited, Unknown author, Optima Magazine, Vol. 4, No. 1, pp. 28-31, (1954). This article recounts the history of diamond mining and the methods used at what is referred to as the “Diamond Coast”.
Beach Mining at the Consolidated Diamond Mines of South-West Africa, Limited: Exploitation of the Area between the High- and Low-Water Marks, D. Borchers, C.G. Stocken and A.E. Dall, Mining and Petroleum Technology – Proceedings of the Ninth Commonwealth Mining and Metallurgical Congress, M.J. Jones (Ed.), Vol. 1, Applied Science Publishers Ltd., Essex, England, pp. 571-590, (1969). Mining along the Namibian coast involves building a dike to keep out the sea, removing the five to twenty-five meters of overlying sand to reach the bedrock, and then using vacuum equipment along the deep channels and gullies in the bedrock where the diamonds are found.
The Third Forbidden City, A. Villers and K. Villers, Diamant Magazine, Vol. 12, No. 119, pp. 15-19, No. 120, pp. 5-6, No. 121, pp. 5-9 and No. 122, pp. 17-19, (1969). The authors describe the mining operations by the Consolidated Diamond Mines Ltd. at Oranjemund near the mouth of the Orange River.
Everything’s Coming up Diamonds, G. Young, Popular Mechanics Magazine, Vol. 133, No. 3, pp. 116-119, 211, 214, and 216, (1970). The operation of the mining ships used along the coast of South Africa and Namibia is described.
Diamonds in the Desert: The story of August Stauch and his Times, O. Levinson, Tafelberg, 172 pp., (1983). This book discusses the discovery of diamonds in the sands of the Namibian desert.
Mining the Desert Foreshore in South West Africa, R.W. Hodgen, Optima Magazine, Vol. 24, No. 2, pp. 90-92, (1974). The author, a former superintendent at Consolidated Diamond Mines Ltd., describes the methods used to recover diamonds beneath the sand overburden along the southern coast of Namibia.
The Transport and Sorting of Diamonds by Fluvial and Marine Processes, D.G. Sutherland, Economic Geology, Vol. 77, No. 7, pp. 1613-1620, (1982). A review of diamond transport and concentration by moving water.
“Diamonds in the Desert – The Story of August Stauch and his Times”, O. Levinson, Tafelberg Publishers Ltd., Cape Town, 172 pp., (1983). This book chronicles the discovery of diamonds in Namibia near Lüderitz, and the subsequent early years of diamond mining along the coast both north and south of the town.
The Story of CDM [Consolidated Diamond Mines] – Diamonds in the Desert, Unknown author, Optima Magazine, Vol. 37, No. 2, pp. 85-92, (1989). The history of the mining company up until recent times is discussed.
Marine Mining of Diamonds off the West Coast of Southern Africa, J.J. Gurney, A.A. Levinson and H. Stuart-Smith, Gems & Gemology, Vol. 27, No. 4, pp. 206-219, (1991). The authors review the history, geologic origin and mining of the marine diamond deposits.
Observations on the Formation of Diamond Placers by Arid Zone Processes within the Sperrgebiet, Namibia, I.B. Corbett, Exploration and Mining Geology, Vol. 4, No. 1, pp. 83-84, (1995). The author discusses the geological conditions which produced the diamond placers along the coast of Namibia.
A Historical Review of De Beers Marine (Pty) Limited’s Role in the Development of Marine Diamond Mining off Southwestern Africa, R.W. Foster, Exploration and Mining Geology, Vol. 4, No. 1, pp. 85-86, (1995). Article not seen.
A Review of Diamondiferous Marine Deposits of Western Southern Africa, I.B. Corbett, Africa Science Review, Vol. 3, pp. 1-18, (1996). Article not seen.
Diamond Desert Memories, J. Van Couvering, Natural History, Vol. 106, No. 10, pp. 16-21, (1997). This article describes the discovery of diamonds in desert gravels near Lüderitz in 1908, which came as a total surprise because of the common belief at the time that diamonds only originated in kimberlite pipes. It also describes a 1975 visit to collect fossils in the Sperrgebiet.
Palaeofluvial Geomorphology in Southern Africa: A Review, E.S.J. Dollar, Progress in Physical Geography, Vol. 22, No. 3, pp. 325-349, (1998). A review is given of the geographic evolution of river systems in southern Africa. These rivers transported diamonds from the kimberlite pipe locations in the interior to Atlantic coastline.
Tertiary-Age Diamondiferous Fluid Deposits of the Lower Orange River Valley, Southwest Africa, R.J. Jacob, B.J. Bluck and J.D. Ward, Economic Geology, Vol. 94, No. 5, pp. 749-758, (1999). This a geological field study of two diamond-bearing gravel terraces exposed along the Orange River. The study revealed the conditions of river transport that produced the diamond deposits.
Post-Gondwana Drainage and the Development of Diamond Placers in Western South Africa, M.C.J. De Wit, Economic Geology, Vol. 94, No. 5, pp. 721-740, (1999). The geologic history of the river drainage systems in southern Africa is discussed in terms of their influence on the formation of diamond placers.
Namibian Marine Diamond Mining, H. Tarras-Wahlberg and M.J. O’Toole, Mining Environmental Management, (July), pp. 12-14, (2000). The authors discuss the regulation and environmental impact of diamond mining.
Recent Developments in Marine Diamond Mining, R.H.T. Garnett, Marine Georesources & Geotechnology, Vol. 20, No. 2, pp. 137-159, (2002). The author reviews the technology and mining methods used to recover diamonds from the ocean bottom along the west coast of southern Africa.
Revival of the Skeleton Coast, R. Baxter-Brown, Rough Diamond Review, No. 3, pp.27-30, (2003). The diamond-mining area is described, along with several theories to account for the origin of the diamonds.
Diamond Mega-Placers: Southern Africa and the Kaapvaal Craton in a Global Context, B.J. Bluck, J.D. Ward and M.C.J. De Wit, Mineral Deposits and Earth Evolution, Geological Society of London, Special Publication, Vol. 248, pp. 213-245, (2005). A diamond mega-placer is defined as a deposit containing more than 50 million carats of diamonds, of which more than 95% are gem quality. The authors describe the one known diamond mega-placer along the coast of southern Africa.
Characteristics of Diamondiferous Plio-Pleistocene Littoral Deposits within the Palaeo-Orange River Mouth, Namibia, R.I. Spaggiari, B.J. Bluck and J.D. Ward, Ore Geology Reviews, Vol. 28, No. 4, pp. 475-492, (2006). This article provides a geological description of the diamond deposits along the Namibian coast.
Some Observations on Diamondiferous Bedrock Gully Trapsites on Late Cainozoic, Marine-Cut Platforms of the Sperrgebiet, Namibia, J. Jacob, J.D. Ward, B.J. Bluck, R.A. Scholz and H.E. Frimmel, Ore Geology Reviews, Vol. 28, No. 4, pp. 493-506, (2006). The richest diamond placer deposits are found in the gullied and potholed portions of the bedrock which lie beneath beach sands along the coast of Namibia. While being carried northward by near-shore ocean currents, the diamonds became lodged in these bedrock trapsites. The authors provide a geologic description of these trapsites and their formation.
The Orange River, Southern Africa: An Extreme Example of a Wave-Dominated Sediment Dispersal System in the South Atlantic Ocean, B.J. Bluck, J.D. Ward, J. Cartwright and R. Swart, Journal of the Geological Society of London, Vol. 164, No. 2, pp. 341-351, (2007). A description is given of the Orange River drainage system and its evolution over geologic time.
Diamond Provenance Studies from 40Ar/39Ar Dating of Clinopyroxene Inclusions: An Example from the West Coast of Namibia, D. Phillips and J.W. Harris, Lithos, Vol. 112, Supplement 2, pp. 793-805, (2009). Dating of mineral inclusions in detrital diamonds gives ages consistent with the period of kimberlite eruption in South Africa rather than the diamonds coming from other geologically older sources.
Ultra-Long Distance Littoral Transport of Orange Sand and Provenance of the Skeleton Coast Erg (Namibia), E. Garzanti, P. Vermeesch, S. Andò, M. Lustrino, M. Padoan and G. Vezzoli, Marine Geology, Vol. 357, (1 November), pp. 25-36, (2014). Geologic study of beach sands in Namibia demonstrates that they were carried as far northward as southern Angola by a strong ocean current. The authors conclude that the Namibian diamonds found in placer deposits along the coast were all derived by transport from the Orange River.
Fishing for Namibian Diamonds, G. du Venage, African Mining, Vol. 21, No. 8, pp. 54-59, (2014). The technology employed to recover diamonds from the ocean floor along the coast of South Africa and Namibia is discussed.
Dr. James Shigley is a distinguished research fellow at the Gemological Institute of America in Carlsbad, California.