That knife really wasn't old, just abused. I was not about to let some dried-up mud get the best of me. I got many theraputic hours of peace and quiet (and a few minutes of swearing) rescuing that knife.
My grandfather's pocket knife, OTOH, is old and abused. I was able to open the blades enough to see that he ground most of the blade away. It just sits on a shelf now.
Some old stuff was carefully maintained. My uncle's Colt M1917 .45 revolver "followed him home" after WW1. It's now in my bailout bag.
What's a bail bag?