Inquiry Regarding Different color rust on helmet

[Tinhat]

Rusting is a chemical reaction and like all forms of science is dependent on the variables. For a relic helmet showing two colors on the same shell that would include, how and over what period of time it was buried and which orientation. Whether the outer shell had a secondary paint would also affect corrosion rates for inner and outer. The bowl of the shell invariably looks different, this is probably linked to the liner leather and band all contributing to a different chemical soup or affecting the timeline, and without getting too gory, the grim reality is that some of these could have well been found with a skull inside.

I think the term of ‘yellow’ or ‘orange’ rust is normally used in identifying a helmet chemically rusted to appear old and therefore ‘new’ rust which may be an oversimplification - there is probably a forum for rust enthusiasts, but they will all be weird, not like us.

[VietnamWarNut]

Thanks for the replies!
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