Question

[thisbrightcity.livejournal.com]

This might not be the place to ask this, but...

Has anyone ever come across glue or glue sticks that seemed to have become "rotten"? I've been working on a collage, and I ran out of glue halfway through. I found this jumbo sized(?) glue stick that I probably hadn't opened in about a year and a half, and when opened it, a huge part of it was black. I figured it wasn't safe to use, so I threw it away, but does anyone have any idea what it could have been?

I know it's probably a really stupid question, but I did try to look it up for a little bit with no luck.