The item spawns a chest with the UsedItemRNG so it should be seed-consistent.
In devil, curse and red rooms it spawns red chests.
In sacrifice rooms it spawns spiked chests.
In angel rooms it spawns eternal chests.
In planetariums it spawns mega chests.
In any other rooms it has a 10% chance to spawn locked chests and 90% to spawn "normal" chests.
Normal chests are determined by the game AFAIK so they have a chance to be stone, spiked, mimic, haunted or yes sadly sacks.
It's available in the treasure room and secret room item pools and in greed mode both too.