I'm looking for a synonym for man-made (i.e., not naturally occurring) that doesn't imply it was made by humans. "Fabricated" or "constructed" are the closest I've come, but I'm not very happy with either of them. Does anyone have some other suggestions?
Edit: Thanks for all the great suggestions! To clarify a bit further: what I mean by "natural" would be something like a rock, cliff or mountain, a tree or forest, a stream or natural lake. The word I'm looking for would refer to anything made by some creature, be it a human, animal, ghost or alien.