Headstock on a used guitar. What could have caused this?
 

I'm seeing this on a used guitar without a proper history. Does this look like chipped top layer from an improper nut replacement, crack from a fall and headstock hitting the floor, or crack from drying, or something else? Thanks.

Probably not from drying but certainly all of the above. My guess is that this is a replacement nut and who ever removed the original one took some wood chips with it.

So you probably won't worry about it when buying?

More than likely from pulling the original nut out during a replacement. It’s probably just the lacquer and is fine structurally. At least without any other cracks not shown by the picture.

No not in the least bit. If it plays good, sounds good, the price is right and you like it then go for it. That is not a structural problem at all.

Thank you!