rust, n.Trivia

Rust can kill you. Rusty metal consumes so much oxygen that it can lead to death in confined spaces like holds of ships.

Barns are red due to the mixture of linseed oil, milk, lime, and ferrous oxide used on wood to resist mold and sun damage in the late 1700s

Barns are red because farmers made their own sealant using linseed oil and rust. The rust protects the wood from algae and fungal growth but also colors the mixture red.

Mars' soil is rust colored because it's full of rust