I was reading a [url=http://www.gaiafoundation.org/sites/default/files/PandorasBoxReportFinal.pdf]report[/url] by the Gaia foundation: [quote]As can be seen, the main metals have a remaining lifespan of between 12 and 50-odd years. However, there is no doubt that new technological developments will allow access to new areas in the future, deeper in the ground, and with likely increased consequences for ecosystems and communities – as can be seen with oil and gas. Recycling policies will also largely determine how much reserves are available. One can argue that the huge amounts of metals contained in discarded electronic items constitute reserves in themselves (the so-called “urban mining”). [/quote] All right, y'know, that seems fair enough I suppose. The graph tells us that Bauxite has a remaining life-span of 27 years, and Bauxite is the main resource from which we extract alumina. They even use the correct source; the USGS: [quote]The best figures on actual reserves per metal can be found on the United States Geological Survey (USGS) website.[/quote] However, it would seem they didn't even read the USGS's entire report. The problem lies in the fact that they aren't clearly defining what they mean by "mineral reserves". Mineral reserves aren't a measurement of the total remaining amount of a particular mineral in the environment, it's how much is left in currently-operating mines. For which there is 1.1 billion tons of Bauxite remaining, which will last 27 years as the report states. However, the [url=http://minerals.usgs.gov/minerals/pubs/commodity/bauxite/mcs-2014-bauxi.pdf]correct[/url] figure for the amount of Bauxite left in the environment is: [quote]Bauxite resources are estimated to be 55 to 75 billion tons, in Africa (32%), Oceania (23%), South America and the Caribbean (21%), Asia (18%), and elsewhere (6%).[/quote] And after doing some really shitty maths (I divided 55 billion by 70 million (the yearly depletion number plus net reduction)) it turns out that's enough to last another eight centuries. I might have fuc­ked up the maths there, but there's no denying that the true figure of Bauxite resources is ludicrously higher than the GF's twisted statistics. But, it doesn't really matter anyway when it comes to aluminium because, as the USGS says: [quote]Domestic resources of bauxite are inadequate to meet long-term U.S. demand, but the United States and most other major aluminum-producing countries have essentially inexhaustible subeconomic resources of aluminum in materials other than bauxite. [/quote]