Shelf Life of Cyanotype Stock?

[tgtaylor]

I'm still working from a stock solution that I mixed from scratch 19 month ago (March, 2015). I wonder how long it lasts?

Thomas

[Ironage]

When I use distilled water and amber glass bottles the solution has always remained good until it is used up. Even when it has been years.

[stawastawa]

I assume you both are referring to parts A and B? or to mixed a and b together?

My understanding is seperate and protected from light they will last a looong time.

[Vaughn]

The Ferric ammonium citrate can get moldy after awhile. I have just filtered it.