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gosub100yesterday at 10:46 PM1 replyview on HN

I remember reading a long time ago about why barns / shipping containers are dark red. and IIRC it's simply because it's a very similar tone to iron oxide and thus the dye was cheapest to produce.


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jasonwatkinspdxyesterday at 11:44 PM

Not quite right.

Iron oxide is anti-microbial. So a barn painted with it as a pigment will last longer vs mold and such.

It's also why large ships all have that red paint color below the waterline. In that case it's copper oxide, which helps slow barnacle growth and similar.

Back in the age of sail they even went as far as copper sheet cladding to make the wooden hulls last longer. Copper oxide pigment emerged toward the end of the age of sail / beginning of the steamship era as a more practical alternative.