Vermiculite deposits in the Palaboroa area, N. E. Transvaal - Schwellnus, C. M. (Carl Martin), 1911- (Pretoria, The Government Printer, 1938)
At head of title: ... Union of South Africa. Department of Mines.
Bibliographical foot-notes.
Keywords: Vermiculite; Mines and mineral resources -- South Africa -- Transvaal