from Los Angeles Times
Treasure of an island cruises the rivers around Manhattan
go to article

How does one go about "preserving" an unrealised artwork? The (re)construction of Robert Smithson's Floating Island, which had remained as a sketch since the death of the artist, is an interesting take on preserving an artist's idea as against the final physical materials of the work. There is also a video of the project on Whitney Museum's web-page.