THE GOLDEN SEMICIRCLE
to the production stage, anxiety as to the continued hfe of the mining
industry persisted; nor is it difficult to find the reason. As Ernest
Oppenheimer put it in the passage just quoted, the Rand was 'really a
low grade field'.
other words, there was not much room for manoeuvre: there were too many
mines always on the 'margin of cultivation', so that a slight rise in
costs, taking into account the average grade, might render a large
number of mines unpayable; on the other hand, just because the number
of mines at the margin was considerable, a relatively small reduction
of costs might exercise a disproportionately favourable influence on the profitability of mining.
Robert Kotze's estimates have already been quoted: they were followed
in 1930 by new estimates of the future gold production of the Union,
prepared by his successor as Government Mining Engineer, Dr. Hans
Pirow. On various assumptions, viz. that the life of producing
mines, as estimated for income tax purposes, could be increased by some
15 to 20 per cent, that costs would remain constant, that a full supply
of labour would reduce costs by 25. a ton and that between 1935 and
1940 six new mines would start crushing, Dr. Pirow estimated that gold
output would be £43,500,000 in 1930, £25,500,000 in 1940 and only £10,000,000 in 1950.14
These were startling figures: gold output, over a period of twenty
years, would have fallen by three-quarters. Further investigation was
clearly necessary, and on 15 August 1930 Government set up a new Low
Grade Ore Commission of Inquiry,15 the terms of reference
being 'to inquire into and report upon the mining of low grade ore on
the Witwatersrand and matters in connexion therewith'. It issued an
interim report on 13 March 1931, recommending the 'immediate grant of
permission to the gold mines to employ Natives from north of latitude
22 degrees south' on certain conditions. The tone of urgency is
explicable by facts which were set out in the final report. First, in
1930, the year in which the commission was appointed, out of the
thirty-two producing mines which were members of the Chamber of Mines,
1 worked at a loss.
7 worked at a working profit per ton milled of less than 25.
5 worked at a working profit per ton milled of between 25. and 3s.
1 worked at a working profit per ton milled of between 35. and 4s.
1411 Official Year Book of the Union of South Africa, pp. 1111-12. 15 Report issued as U.G. 16 of 1932.