Some time ago I had a brain burp and bought myself a half pan of Manganese Blue. It was a beautiful colour blue and whatsmore it was one of those watercolour pigments that you could use to get some spectacular granulated effects.
The trouble was, it was quite expensive and I was afraid to use it. I know that sounds ridiculous but not as ridiculous as this. I'm not sure how long I had it but I kept it in an old paintbox with some other colours I didn't use much. I always reminded myself it was there and would know exactly how to find it once the occasion for the use of Manganese Blue arose.
Ta-Da! That occasion was today. I was painting this lovely sky which needed a jewel-like streak of Manganese Blue running through it. I dug out the paintbox which my prized Manganese Blue was resting in and excitedly opened it up.
But, but, but where was it? Where was my half pan of Manganese Blue? I promise this is true, it had simply dried out to virtually nothing but a few grains of powder and dried out gum arabic crystals.
I had kept it for far too long, maybe five years. My thrifty idea for saving materials had backfired on me again. I'm going to check out all my tubed colours now and make sure that none are getting to the point where they start to solidify. You won't find me tearing open the lead tubes in future, trying to save a little bit of solid pigment. Then again, until I've checked my stock, I may have to.
Don't forget, keep your brush moist, and don't let the water run down the ferrule. Happy Painting.