No clue as I'm just getting to that part but is it maybe for one of those levers by the mine elevators. There is always a levered switch on the left by them but pulling it never seems to do anything.
Plus there is a part in the game where you need a broken lever part in a fire spitting room in Orobas fjords. Not sure if you got there yet but maybe it is a spare for that part if you miss the one in that room or something.
Could be part of a side quest as well. I have all kinds of things for side quest in my backpack that I have not even gotten the quests for yet.
I've had something called Linda's purse in my backpack for most of the game and have not met a Linda yet that I know of or anyone to even give me a option to say I found this purse in anyone's dialog.
Good thing I'm playing as a female or else I would've gotten rid of it a long time ago if I was playing male.
Carrying a purse around the whole game.
