New FAQ - Update suggestions and Corrections Thread

[mrerick]

From Heinz,

I was looking at the FAQ on cold blue. I believe it has an error. The copper compound with the smell is copper selenide, the same chemical that gives garlic its smell. Commercial cold-bluing compounds contain selenium often as selenious acid. The chemical reaction with the copper sulfate in the bluing solution when applied to iron, forms a copper selenide black plating on the metal