I have a small bottle of Ammonium Dichromate in solution that is about 2 years old from a cyanotype kit that I have never used yet. It has just been sitting in a box in a bag in a dark area for that amount of time. How light sensitive is this chemical solution by itself, before it is mixed with the other dry chemicals in the kit? Would it still be any good after after aging and minimal exposure to indirect light that is probably stronger than recommended when all the chemicals are mixed? It has not been mixed yet, so I just want to know if it can still be used to make the cyanotype solution.