"Art is generally understood as any activity or product done by people with a communicative or aesthetic purpose—something that expresses an idea, an emotion or, more generally, a world view."
You are looking for a nano. The question to answer, "Is this art?" It was made by man and to some could be considered art. You can decide when you find it.
BYOP
When you put this cache back in its hiding spot please make sure to put the magnet on to the hidden metal plate. It make is easier for the next person to find it. You cannot see the metal plate but you can feel it. This plate is what keeps the cache container in its place.