|Do we have adequate metals for the future?|
Minerals and metals are part of our lives. Mineral products are components of our homes: foundations, chimneys, bricks, insulation, electric wiring, plumbing, interior walls and glass; appliances, pots and pans, dishes, cutlery, electronics and other products. Food comes in steel, aluminum and glass containers. Our workplaces are almost entirely constructed of minerals - concrete, steel, copper and glass. Our vehicles are chiefly made of metal.
On a global basis, there appear to be sufficient supplies of non-metallic minerals. Will our children and their descendants have adequate supplies of metals, however? Ore reserves at existing metal mines are finite. Should we cut back on consumption to preserve them for future generations? The answer to this question has several facets.
The first concerns ore reserves - these data are not essentially helpful because they constitute only a tiny fraction of the world's total stock of known and undiscovered mineral deposits. Most mines will yield more metal than is counted in current reserves. As metal consumption has increased, world ore reserves have increased, not only because of discoveries, but because of developments in mining technology that have lowered production costs - large mechanized mining equipment, less expensive bulk explosives and large milling and concentrating equipment. Such developments have made it possible to recover metals from deposits whose low grade previously prevented them from being profitably mined. There may be limits to technological advances, but we have yet to reach them.
In addition to mines, the world has a large inventory of known deposits not economically mineable today. In Canada, one of the world's major mining nations, near-economic deposits contain, in total, twice the tonnages of metal already produced or remaining to be produced from past and present mines. The same is likely true elsewhere. Future technological developments will turn some of these deposits into mines.
Another facet is price. If demand for a metal were to increase to levels that outstrip existing supply, the market would drive the price up, thus making it possible to convert many uneconomic deposits into viable mines. It would appear, however, that supply relative to demand has been more than adequate, given that the constant-dollar price of many metals has been declining for the past several decades.
New orebodies continue to be discovered, even in regions where mining has gone on for centuries, although typically at a declining rate. Scientific and technological developments in exploration have made it possible to discover hidden and deeply buried deposits. Further exploration improvements should provide a continuing supply of discoveries, even in many well-explored regions.
Extensive areas of the world have been only superficially explored for metals, yet have high discovery potential, for example the South Pacific, parts of South and Central America, parts of Northern Canada and much of Africa. In Chile, a major copper-producing nation for over 100 years, copper production increased from 548 000 tonnes in 1961 to 3 116 000 tonnes in 1996, soon to be 5 000 000 tonnes. From 1961 to 1996, world copper output grew by a factor of 2.5 and is still increasing. Production of most other metals has grown similarly, and no shortages are in sight for any metal.
Metals are recyclable and as such remain available for future generations. Some 40% of current world copper consumption comes from recycling. This does not mean that 60% of copper is wasted - only that, on average, it takes decades for copper to complete its useful life and be recycled. By that time, world production has risen, creating the illusion that only 40% is being recycled. In fact, the actual percentage is probably close to 90%.
Some 47% of world lead consumption is from recycled lead. Lead-acid batteries represent 70% of lead consumption in the Western world. Some OECD countries recycle well over 90% of battery lead. More than 50% of the world's steel is recycled material, as are major percentages of most other metals.
Much can be done to increase the recycling of post-consumer metal. Unlike most other new materials used in manufacturing, metals lend themselves to continuous recycling. Working towards higher levels of metal recycling is another way to help to ensure that future generations will continue to have adequate supplies of the metals they will need. Nevertheless, even at conservative assumptions of world population growth and economic development, new sources of metal will continue to be needed. One can anticipate that future generations may have to manage with less metal per capita, but world metal supplies seem to be assured for at least the next century, as far into the future as anybody can possibly foresee.