DWM Rust Bluing Formula??

[pipeman45]

Originally posted by Rod WMG
I grew up around milk cows, but not machines; it was all done by hand by the people I knew. Please educate me about what "milkstone" is. I assume it is when the milk hardened with exposure to air.

I think it's a combination of the calcium and the milk fat. Being a dumb farm boy I not real sure.It forms up like a rock,and it's darn hard to remove!!!