I brought a lichen covered bench from Cornwall where it had been overlooking the sea high on the top of the cliff where the air was pure. It has been here for about four years now. I don't think it's lost any lichen due to the atmosphere here, just to the animals and people who try to sit on it.
I also brought a staddlestone which arrived here from Gloucestershire via Cornwall and used to belong to my mother. I put earth in the dips in the stone surface and planted sempervivum which seems to flourish in it's new home.