I experienced a similar thing to MGM.
Many years ago I was working with a colleague in a print room (4m x 4m with one entrance). We 'lost' a pair of large scissors that we had been using. There was minimal furniture in the room. After 15 minutes of a rigorous & futile search, it suddenly 're-appeared' on the top of an empty table in the centre of the room. Nobody had entered the room or left the room & I am 100% confident that the colleague wasn't pulling my leg. I don't make any claims to this mystery being supernatural however, I remain totally baffled by it to this day.

Incidentally,my late mother-in-law had a similar experience with the disappearance of a tea set from a bedroom cupboard. It re-appeared in its original place a year later. The cupboard had been emptied & searched my her & her husband when the tea set originally vanished. Go figure.