The other point is that anodising usually fails if something goes over 80 oC.

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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.

FORBES: It's The iPhone 5's Aluminum Case That's Causing Problems For Apple and Foxconn

Anodising is a process where we deliberately increase that layer of oxide.

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There are, in theory, two ways you could do this anodising.

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