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Aluminiumis a chemical element, with symbol Al and atomic number 13. It accounts for 1.5% of the total mass of the planet. It is chiefly extracted from bauxite, other rocks containing insufficient amounts for profitable exploitation. Aluminium is the twentieth non-renewable resource set to disappear thanks to intensive exploitation by mankind. Remaining workable deposits of bauxite (the principal aluminium ore) are estimated at 25 billion tonnes. June 2008: at current rates of production, 190 million tonnes per year, deposits will last 131 years. Extractable deposits of this metal will therefore disappear for good in 2139. This information comes mainly from the USGS (United States Geological Service) http://minerals.usgs.gov/ This date is only a rough indication. Sources differ, and it could change with the evolution of our civilisation. Applications: transport: 30%, building and construction: 18%, packaging: 17%, consumer goods: 6%, miscellaneous: 29%. Problems arising from its disappearance will start to make themselves felt well before this fateful date. On this subject, see Hubbert's peak theory: https://en.wikipedia.org/wiki/ Of course, there will still be aluminium in the ground, but in extremely diluted form, rendering extraction impossible. |
Even if, thanks to advances in technology, we find new deposits by digging deeper and deeper into the Earth's crust, this will afford us only a few years' reprieve and will not make a major impact on the situation. Aluminium was created when a star exploded and the Sun and the Earth were formed from the debris, over five billion years ago. You cannot produce it artificially and there is no substitute. The Moon and the asteroids do not contain the metal in an extractable form. And just imagine the energy it would take to bring some back from Mars or Venus! Note that aluminium (3%) could be extracted from polymetallic nodules present on the ocean floor, at depths of several kilometres. The total quantity of polymetallic nodules on the ocean bed was estimated at over 500 billion tonnes by A.A. Archer in 1981. However, given the depths at which they occur, these deposits are not profitably recoverable. There will still be recycling but demand, which will keep growing exponentially with the development of the emerging economies, will far outstrip supply. 30% of the world's known bauxite reserves are located in the Republic of Guinea. Australia: 23%. Jamaica: 8%. Cuba: 8%.
To learn more about aluminium, see: http://fr.wikipedia.org/wiki/Aluminium
Translation Nicholas ROSE ![]() |
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