All About Pocket Knives

The Colonial is probably fine. I see shrinking and cracking, but not much corrosion or damage.
I know of no way to preserve or restore celluloid once it has started to break down. Your best bet is to have them rehandled in Acrylic if you want them to look close to original, or in anything else that you want if you only want them to be useable again.

My outgassing contribution to this topic or thread.
The main handle side says/said, "PAYNE MOTOR CO."
The other handle side says/said, "PAIGE - JEWETT"
I had no, nor do I have, any intention of repairing or restoring this pocket knife.
I did NOT have to clean ANY of the metal parts after the removal of the handles.
Caption(s), if any, are on the BOTTOM of the corresponding picture(s).
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