A special use for chainmail armor – The chainmail helmet should instabreak sand/gravel falling on top of the player.

The chainmail armor is basically a sieve, and so breaking sand/gravel into small bits and converting it to a block makes sense.

This adds to the game the same way leather boots being able to walk on powdered snow does.

Falling gravel is an annoyance and collecting sand can also be irritating early game, an unorthodox solution to this is placing a torch. This is basically an easier way to do the same thing. And plus it gives the forgotten chainmail armor a unique yet useful purpose.