Once a work of art is finished it is difficult to imagine that at some point in history it could have been different.
Reading this article, it is interesting to know that the Guggenheim was not always the bright white color with which we can observe it today, the original color used to be beige, and after the addition of the building that was made in 1992 The city’s Landmarks Commission agreed to change the color of the façade, a decision that is not very respectful with the author of the work, I must say
I have not found quality color photographs prior to 1992 but doing a little simulation with Photoshop, it should be something like this:
And deepening even more in the other colors that Wright had in mind for this famous museum, it is fun to imagine what the building would be like if Wright had decided to finish it in one of the other colors he studied:
but returning to the original color, let´s hope that one day the same authorities that have decided to change Wright’s work in such an arbitrary way will return to this building the color that it should never have lost.
More information, and debate, in this thread.