I also had these instructions from the workshops that I did with Carol and Linda in their Fibre in Form workshop.
I didn't like the idea of using these chemicals although they all assured me it was safe to do so.
Knowing what I am like I thought I would do myself some harm and my husband felt the same as well.
Then I remembered that someone years ago had told me about using steel wool and water and vinegar so I decided to use this method instead.
In the first photo the rust is very crusty and has a wonderful texture.
This photo is of the last piece of paper that I put in the sludge that was left--it turned out very even in the colour.
I bet if I tried to get the same effect again I wouldn't be able to.
In this piece I turned the paper around and also over so that I got a very nice variation in colour.