The scrap bin at my local thrift store, holder of all manner of used metals, is stocked better on some days than others. Trooped home with these recently and although caked up with goo, dirt, and who knows what else, they were a good find. Stuck the whole lot in an acidic brew intended to eat away the whatevers, set the pot on the chest freezer in the pantry ... and then completely forgot about it.
Whoops. Hadn't meant to create rust, but this could be advantageous.
Except that a very discernible sheen of mystery oil something-or-other is floating on the surface which doesn't look too promising. Since all these bolts & washers were dunked with the purpose of a good scrub [covered in unknown industrial grease & grime], I'm tossing this liquid mess for now. Dunno what it is and that makes me a tad nervous. Luckily, this process is repeatable. Here's the recipe for next time should anyone find the portions helpful:
two parts water
to one part vinegar.
wait two weeks ...
[use a dye pot, or pail, etc. NOT a cooking pot from the kitchen]
... iron mordant.
Mordant = from the Latin verb 'mordre' which literally means 'to bite';
mordant helps the dye 'bite' into fiber.
A quick search on the internet has revealed that one can use iron liquor as a mordant by straining the solution into a stainless steel pot (that is, if one does not have an iron pot at hand to begin with) and after adding water, then add your pre-wetted fibers. A short simmer of ten minutes or so, followed by a natural cool down in the solution and a thorough rinse at the end. The fiber is "fixed" and both light-fastness and wash-fastness is improved when using most natural dyes. Colors may well be altered - iron, also know as the great "sadden-er" produces quite beautiful results, turning some reds into deep Egyptian purples and some browns into shades of gray and brown-blacks.
HERE is a quite interesting tale on the same subject.
And after all that,
there's still the rusty bits to play with ...