Detect if a block wasn't placed by player

Hello, I am making a mod for minecraft 1.16.5 that spawns custom loot chests, and I would like to know if it's possible to detect if a block wasn't placed by a player without hardcoding.

I need this so the mod can know if the chest spawned naturally or was placed so you can't just dupe the loot by placing and breaking the block over and over.

Thanks for reading