I had bought poster/water colours a year ago (because of the persuasion of our school) but never had an opportunity to use it, because my previous box of colours were what I used during the whole academic year. Now that I have free time in my hand, I want to paint some drawings I drew in my free time, and those I am currently drawing. However my paint bottles have dried up over the year. Now I don't want to simply throw away the completely filled bottles just like that.
Is there a way to recover those colours? I don't think addition of water alone would essentially help, because I had tried that when I was young with some other colour bottle, but it just made it extra watery and the vividness of the colours were lost.