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A.J.A. (Bram) Janse

Adjunct Senior Research Fellow

School of Earth Sciences - Centre for Exploration Targeting

Contact details

+61 9447 5233


Bram Janse is an internationally known diamond exploration geologist who has accumulated more than 50 years of experience in mineral exploration, specializing in diamond exploration on all continents. After graduating from the University of Leiden (The Netherlands) with a degree of Drs in 1955 and after having spent several years in the field in South Africa and Namibia searching for diamonds and kimberlites in the employ of Anglo American-De Beers subsidiaries, he obtained a Ph.D. degree from the University of Leeds (England) in 1964 for his research on the Gibeon kimberlite field and the Brukkaros alkaline complex in Namibia. From 1965 to 1980 he was employed by Selection Trust (London), which in 1980 merged into the BP Minerals group and until the end of 1985 he was Group Consultant Geologist (Diamonds) for BP Minerals International Ltd in which capacity he inspected many diamond prospects around the world.

Since the mid 1980’s he has managed his own geological consultancy company, ARCHON Exploration Pty Ltd, based in Perth, Western Australia, concentrating on diamond exploration in Brazil, Canada, India, South Africa and the United States. He was a consultant to, and was from time to time a director of, several Australian, Canadian and US exploration companies. He was an Honorary Research Associate of the School of Earth Sciences (Geology) of Macquarie University in Sydney, Australia, and is a speaker on diamond exploration at many conferences and symposia in Australia, Canada, the United States and elsewhere. At present he is a consultant to Australian Indian Resources Pty Ltd, exploring for diamonds and precious and base metals in India. Bram was the organizer of the poster session of the Fourth International Kimberlite Conference, held in Perth in 1986, and editor of the section on diamond exploration in the proceedings volume published in 1989.

Bram's main field of expertise is in all aspects of diamond exploration related to primary sources and alluvial and marine deposits. He has advised on area selection, exploration, mining and valuation of these deposits throughout the world. This work includes original on-going research of alkaline and ultrabasic rocks which resulted in about 120 published papers and numerous in-house research reports. He has compiled an extensive database of diamond and kimberlite occurrences around the world and has a large collection of books, pamphlets and brochures on diamond, diamond exploration, kimberlite/lamproite primary host rocks and diamond related subjects. He is fond to talk about how diamonds, and searching for diamonds, are represented in the professional and casual literature and about the many misconceptions that writers portray in their stories. Following in the footsteps of his late friend and mentor, John Sinkankas of San Diego, author of ‘Gemology, an annotated bibliography’, Bram is in the process of writing commentaries on the 2,500 diamond books he has read or collected. With the help of many friends and colleagues he is compiling an inventory of all the world’s kimberlites and lamproites, listing their location, rock types, structural/tectonic setting, country rock environment and special features.

Bram is a Fellow of the Geological Society (London), and the Australasian Institute of Mining and Metallurgy, a member of the Institution of Mining and Metallurgy (London), the Canadian Institute of Mining and Metallurgy, the American Institute of Mining and Metallurgical Engineers, the Geological Society of Australia, the Prospectors and Developers Association of Canada, a Chartered Engineer (London), a Chartered Geologist (London) and is on the editorial board of Gems & Gemology, the quarterly periodical of the Gemological Institute of America.


Janse, Bram, 2013. Ups and downs. London: Mining Journal, September 13, 2013, pp. 18-26.

Janse, Bram, 2012. Diamond market turns opaque. London: Mining Journal, September 7, 2012, pp. 16-19.

Janse, Bram, 2011. Diamond recovery. London: Mining Journal, September 9, 2011, pp. 21-25.

Shigley, James E.; Laurs, Brendan H.; Janse, A J A (Bram); Eden, Sheryl & Dirlam Dona M, 2010. Gem localities of the 2000s. Gems & Gemology, vol 46, no 3, Fall 2010, pp. 188-216.

Janse, Bram, 2010. The sparkle continues. London: Mining Journal, September 10, 2010, pp. 12-17.

Janse, Bram, 2009. Diamonds search for new best friend. Mining Journal, September 11, 2009, pp. 18-25.

Read, George H., Janse, A.J.A. (Bram), 2009. Diamonds: Exploration, mining and marketing. Lithos, vol 112S, part 1, pp. 1-9.

Janse, Bram, 2008. Diamonds in a temporary equilibrium. Mining Journal, August 22, 2008, pp. 20-25.

Janse, Bram, 2007. New sources needed to keep diamonds sparkling. Mining Journal, August 31, 2007, pp. 20-25.

Janse, A J A (Bram), 2007. Global rough diamond production since 1870. Gems & Gemology, vol 43, no 2, Summer 2007, pp. 98-119.

Janse, Bram, 2006. Diamond exploration. London: Mining Journal, August 18, 2006, pp. 19-26

Grégoire, M., Rabinowicz, M. and Janse, A.J.A., 2006. Mantle mush compaction: a key to understand the mechanisms of concentration of kimberlite melts and initiation of swarms of kimberlite dykes. Journal of Petrology, vol 47, pt 3, pp. 631-646.

Janse, Bram, 2005. The search for diamonds. London: Mining Journal, August 19, 2005, pp. 18-25.

Janse, Bram, 2005. Diamond shortfall spurs exploration. London: Mining Journal, January 28, 2005, pp 17-20.

Janse, A.J.A., 2004. Diamonds. In: Mining Annual Review 2004. London: Mining Communications (issued on CD-Rom only), 16 p.

Janse, A.J.A., 2003. Diamonds. In: Mining Annual Review 2003. London: Mining Communications (issued on CD-Rom only), 16 p.

Janse, A.J.A., 2002. Diamonds. In: Mining Annual Review 2002. London: Mining Journal Press (issued on CD-Rom only), 12 p.

Janse, A.J.A., 2001. Diamond exploration overview. In: Mining Journal, August 17, 2001, vol 337, no 8647, pp. 116-121.

Janse, A.J.A., 1998. Diamonds in Africa. In: Vearncombe, S. and Ho, S.E., editors, Africa: geology and mineral exploration, Proceedings of the AIG seminar, held Perth, November 6, 1998, pp. 51-60. Perth: Australian Institute of Geoscientists Bulletin No. 25, 89 p.

Janse, A.J.A., 1996. A History of Diamond Sources In Africa: part II. Gems & Gemology, vol. 35, no. 1 (Spring 1996), pp. 2-30.

Janse, A.J.A., 1995. A History of Diamond Sources In Africa: part I. Gems & Gemology, vol. 34, no. 4 (Winter 1995), pp. 228-255.

Janse, A.J.A. and Sheahan, P.A., 1995. Catalogue of world wide diamond and kimberlite occurrences: a selective and annotative approach. In: W.L. Griffin, (editor), Diamond Exploration: Into the 21st Century. Special Volume Journal of Geochemical Exploration, vol. 53 (1995), pp. 77-111.

Janse, A.J.A., 1994a. Is Clifford’s Rule still valid? Affirmative examples from around the world. In: H.O.A. Meyer and O. Leonardos, (Editors), Proceedings of the Fifth International Kimberlite Conference 2, Diamonds: Characterization, Genesis and Exploration, pp. 215-235. Departamento Nacional da Produção Mineral, Brasília, 390 p.

Janse, A.J.A., 1994b. Review of supposedly non-kimberlitic and non-lamproitic diamond host rocks. In: H.O.A. Meyer and O. Leonardos, (Editors), Proceedings of the Fifth International Kimberlite Conference 2, Diamonds: Characterization, Genesis and Exploration, pp. 144-159. Departamento Nacional da Produção Mineral, Brasília, 390 p.

Garanin, V.K., Kudryavtseva, G.P. and Janse, A.J.A., 1993. Vertical and horizontal zoning of kimberlites. In: Y.T. Maurice, (Editor), Proceedings of the Eighth Quadrennial IAGOD Symposium, held Ottawa, Canada, August 1990, pp. 435-443. Schweizerbart’sche Verlagsbuchhandlung, Stuttgart, 900 p.

Atkinson, W.J., Smith, C.B., Danchin, R.V. and Janse, A.J.A., 1990. Diamond Deposits of Australia. In: Hughes, F.E., editor, Geology of the Mineral Deposits of Australia Papua New Guinea, pp. 69-76. Monograph no 14, Vol. 1. The Australasian Institute of Mining and Metallurgy, Melbourne

Janse, A.J.A., Downie, I.F., Reed, L.E. and Sinclair, I.G.L., 1989. Alkaline intrusions in the Hudson Bay Lowlands, Canada: Exploration methods, Petrology and Geochemistry. In: Ross, J., (Editor), Kimberlites and Related Rocks, Vol. 2: Their Mantle/Crust Setting, Diamonds and Diamond Exploration, pp. 1192-1203.  Geological Society of Australia, Special Publication no 14, 622 p.

Janse, A.J.A., 1989. Editor of Section VI: Diamond Exploration. In: Ross, J., Chief Editor, Kimberlites and Related Rocks, Vol 2: Their Mantle/Crust Setting, Diamonds and Diamond Exploration. Geological Society of Australia, Special Publication no 14, 622 p.

Janse, A.J.A., 1984. Kimberlites, Where and When? In: J.E. Glover and P.G. Harris, (Editors), Kimberlite Occurrence and Origin: A basis for conceptual models in exploration, pp. 19-62. Department of Geology and University Extension, University of Western Australia, Publication no. 8, Perth, 298 p.

Janse, A.J.A., 1975. Kimberlites and related rocks from the Nama Plateau of South West Africa. In: L.H. Ahrens, J.B. Dawson, A.R. Duncan and A.J. Erlank, editors: Proceedings of the First International Conference on Kimberlites, held Cape Town, September 1973. Physics and Chemistry of the Earth, vol 9, pp. 81-94. Oxford: Pergamon Press, one volume, 940 p.

Janse, A.J.A., 1971. Monticellite bearing porphyritic peridotite from Gross Brukkaros, South West Africa. Geol. Soc. Sth. Afr. Trans., vol. 74, no. 2, pp. 45-55.

Janse, A.J.A., 1969. Gross Brukkaros, a probable carbonatite volcano in the Nama Plateau of South West Africa. Geol. Soc. Amer. Bull., vol. 80, no. 4, pp. 573-586.