Handling an iPhone 5 will definitely remove some portion of that layer of aluminium oxide.

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Thus gives you alumina, aluminium oxide, which you then put through a smelter to make aluminium metal.

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And the reason why you need two tonnes to make one tonne is that alumina is aluminium oxide (Al2O3).

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Either high or low ph environments will strip the anodising (what is effectively a layer of aluminium oxide) from the underlying metal.

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They created a material that excluded light with a wavelength of one millimetre (the long end of the infra-red spectrum), using an array of aluminium-oxide posts that were spaced evenly across a grid.

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Thermite is a substance that can literally melt steel and is made up of iron oxide and aluminium.

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In 2010 a team of researchers from Washington State University found that artificial regolith containing silicon, aluminium, calcium, iron and magnesium oxide could be used by 3D printers to create solid objects.

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