‘MINERAL RESERVES NOT SO SMALL’

Press, Volume CXIV, Issue 33539, 21 May 1974, Page 14

‘MINERAL RESERVES NOT SO SMALL’

The future of mineral resources may not be as gloomy as is sometimes forecast. Professor A. L. Titchener. of the University of Auckland’s chemical and materials engineering department, said yesterday when giving the opening address at the Australasian Institute of Metals conference in Christchurch.

Professor Titchener said numerous estimates had purported to demonstrate that many mineral resources would be exhausted in a few more years. These computations were; based on, among other things, published or estimated

lvalues of cunent universal I (reserves. Those making the’ computations had usually' ! misunderstood the special ■ l warning given to the term; : “reserves” by mining engtn-i leers and economic geologists J j “Reserves are quantitiesi iof ore known to exist and] (economic to mine,” said l Professor Titchener. “They! do not include deposits as!

I yet undiscovered, or deposits [known to exist but unecon(omical to mine.’’ ; Professor Titchener said 'Calculations based on known i reserves yielded unrealistically short estimates of the I life expectancy of a resource A good example wa« ‘petroleum. In 1940 the world’s petrolleum reserves were sufficient Ito last about 20 years at the then rate of consumption Today, 34 years later, petroleum reserves were sufficient to last about 20 years at the present rate of consumption, which was about 10 times that of 1940.

"This does not mean, of course, that we don’t have to worry about the supply of oil. We do have to worry, and not only for reasons connected with international politics,” said Professor Titchener.

“Supplies of oil clearly are exhaustible. They may become exhausted quite soon. But one thing is quite certain: we do not know how much oil still lies in the ground. It is a lot less than it was, but it may be a lot more than many suppose. “Any estimate we make of the life of any mineral resource will almost inevitably be too short, because they can be based only on discovered resources. Until now these have always been far less than the total resources.”