I have a half-bottle of Accurate 4064 powder; hasn't been opened for several years. I was rummaging through all the shootin' crap I have, and found this bottle of powder to have solidified into a brick of sorts. The humidity is very low where I live, and the cap has been screwed-down tightly for these past several years. No other bottle of powder I have has solidified like has this bottle. Anybody ever seen anything like this in their experiences?