I am a textile artist. I transfer rust from rusty objects onto cotton fabric by spritzing the fabric with vinegar and water, then laying or wrapping the rusty object on the fabric, cover loosely and wait for the process to happen. There is a lot of 'advice' on the net about how to 'neutralize' the rust - which I assume means to arrest the process so it won't continue to eat into the fabric and cause it to degrade. The most common advice is to soak the rusted fabric in a salt water solution. I am not a scientist, so I have no idea - but I do know that exposure to salt promotes the rusting process, so I am having trouble believing that salt water also 'neutralizes' the rust. So my first question is - is this plausible? My second question relates to immersing the rusted fabric in a tannin solution. Fibre artists use a very strong brew of tea for this purpose. Artistically, this is a great process, as it creates a beautiful blue-grey bloom on the fabric and knocks back the rather icky orange colour of the rust. My research has shown that the principal active ingredient in rust neutralisers - such as you buy at the hardware - is tannin. Of course I do understand that these products are designed to be used on rusted metal, not fabric, but I assume it is the interaction between the rust and the tannin that is significant, not the substrate that the rust is on? So my second question is, if I immerse the rusted fabric in a tannin solution does that 'neutralise' the rust? And if so, what exactly does 'neutralise' mean in this context. Thank you in anticipation - and just a reminder - I am not a scientist, I am an artist, so please keep any explanation as layman friendly as possible!