Back when bitcoin mining was a novelty that was still feasible on a decent graphics card, I mined seven bitcoins. I kept everything on an external spinning rust drive. In the process of a move, the external drive was lost to wherever shit goes when you move house.
I've never figured out what happened to it, and for a long time I looked for it. When I used to drink booze I would get buzzed on an occasional weekend and look through my storage unit.
It'll never show back up, and like a lot of things in my life is so far in the past that it is of no use to get all hot n bothered about it. Ships in the night, or whatever.