

Why Are Barns Red? - jeebusroxors
http://www.grit.com/print-article.aspx?id=1284

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pg
Because initially iron oxide was the cheapest pigment. White paint, which
might seem the default choice chromatically, was more expensive to make.

[http://www.osv.org/explore_learn/document_viewer.php?DocID=1...](http://www.osv.org/explore_learn/document_viewer.php?DocID=1888)

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projectileboy
Maybe I'm being obtuse, but I didn't glean from the link why folks simply
didn't opt for _no_ pigment (which I assume results in some sort of
unappealing gray or brown). Do you know why?

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pg
Because the pigment is what protects what's under paint from UV light. With no
pigment you have in effect varnish. Also, without some kind of pigment you
might have to use excessive amounts of binder to get a sufficiently thick
coat.

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projectileboy
Ahh... I was ignorant; I assumed the pigment provided only color. Thanks.

