Farmers originally used to seal their barns with a combination of linseed oil (red-ish) and iron oxide (rust, red). Then when paint came around, apparently red paint was the cheapest. https://www.bobvila.com/articles/solved-why-are-barns-painted-red/
Basically also why Swedish barns are red. I presume those two stories and red barn origins are related.
Not just barns, the stereotypical swedish red houses with white detailing exist pretty much because of a single copper mine in the town Falun, where they got so much leftover product to turn into paint that it basically supplied the entire country even to this day.
https://en.wikipedia.org/wiki/Falu_red
That town also spawned the equally stereotypical (though less internationally known) Falu sausage, which is probably one of the most popular meat products here.
https://en.wikipedia.org/wiki/Falukorv
And lastly to hammer home how insanely important this mine has been: It has been continously mined from like year 800 up until the 90’s, has been the source of a lot of improvements to global mining technology, and as of 2001 it is a UNESCO world heritage site.
It’s honestly kind of weird it’s not more well known, and i HIGHLY recommend visiting the museum and going on a tour through the actual mine itself.You can get there by train comfortably by taking the Snälltåget night train from hamburg (or even berlin) to stockholm and then the SJ intercity to Falun.
Yeah red dye goes a long way and is easy to make
Except car pigments? I hear that they are the most expensive.
That’s because of our evolutionary desire to look for ripe fruit. So, we want red thing.
Source: idk, heard it sopmewhere
Barns are actually moving very quickly away from you causing the light that is reflected off of them to become redshifted.