Recently I dyed fiber with mint leaves from my herb bed and black walnuts collected last autumn by a friend. Although I was pleased with both experiments–it was a first for me with mint and black walnuts–I decided to see what other colors might be produced by over dyeing with iron.
In perusing the many “natural plant” dye books at my local library, as well as those I have purchased on-line, I had read that over dyeing with just a pinch of iron could produce different shades. I divided my fiber lots in half, so I could retain the original black walnut and mint dyed shades.
Firstly, I mixed a concoction of boiling water and half a teaspoon of iron. Then I added the mix to the exhaust baths of each dye, which I had retained in Mason jars. Each pot was simmered separately with mint dyed fiber and iron mix and black walnut fiber and iron mix.
The results: mint with iron produced anything from pearl to steely grays and darker grays, depending on the fiber. Black walnut with iron produced shades of brown, from very light to very dark. (The warmest brown was obtained by the lace).
In my book, this was a successful over-dye session, and shades were about what I expected from the research.