The dried chestnuts looked undamaged in their husk, but three groups of weevil grubs surely left some damage behind:
Gingerly prying the seeds out revealed holes in all three:
The weevils converted the nut meat into what looks like solid frass:
Having eaten themselves out of house and home, they moved on to the next plane of existence.
For most of them, that would be bird food.
The Smell of Molten Projects in the Morning 
Roast those “over an open fire”! … Truth be told, I’ve never had roasted chestnuts of any variety, especially frass flavor.
I vaguely recall eating a roasted chestnut and deciding it didn’t live up to the hype.