The Discovery and Delineation of the Heavy Mineral Sand Orebodies at Graauwduinen, Namaqualand, Republic of South Africa

Exploration & Mining Geology, Vol. 3, No. 4, 1994

G.L. PALMER, Anglo American Corporation of South Africa, Johannesburg, Republic of South Africa

In 1986, anomalous sampling results for heavy minerals were obtained at various sites in Namaqualand on the west coast of the Cape Province. Drilling in 1987 at Graauwduinen penetrated up to 35 meters of heavy mineral-bearing Tertiary sands which extend several kilometers inland from the coast. The heavy mineral suite includes ilmenite, rutile, leucoxene, zircon and monazite, along with garnet, pyroxene and amphibole. Three deposits are recognized, two of which comprise the resource to be mined by Namakwa Sands Limited, a recently formed Anglo American Corporation subsidiary company. Mineable reserves in excess of 500 million tonnes have been delineated, sufficient to sustain mining for over 35 years at projected production rates. During the feasibility study, on-site investigations included test mining at various sites to assess mineability and to provide material for metallurgical testing in a pilot plant located at the site. Ilmenite produced at the mine will be smelted at a new facility to be built at Saldanha Bay. Saleable products comprise titania-rich slag, pig iron, zircon and rutile. During the exploration phase, company environmental guidelines were established and monitored. The feasibility study incorporated a Class 1 Environmental Impact Report, the contents of which were made public following the principles of the Integrated Environmental Management legislation.