I did not realize that getty images were not allowed in this forum, my thread has been nuked
I saw an image last night from 9/11 that showed the top of the Worldwide Plaza with a green roof, which means that the top had oxidized by the 2000s. This means that at some point between 1990 and 2000 the top became green… I don’t know the timing of oxidation for the World Financial Center but perhaps it was the same. So sometime in those 10 years it began changing.
This is an image supposedly from September 1997, by RNRobert on Flickr. I believe you can see the top turning from copper-green, the photo seems to have a filter on it so I cannot say for sure
I’m going to work on collecting images specifically from 1995-2000 to see if I can create a timeline(?) of oxidation. Perhaps I am looking in the wrong places, but it is proving to be difficult to find any high quality images of the west side of Manhattan during this time period. Most of what I’m finding is just of the trade center. Although this image above has a filter on it (or maybe it’s just how the camera is) I cannot be very picky in what types of photos I’m able to find.
The top of the roof was still copper in 1991-92 and it seems that this was the case in 95. Unfortunately this image above does not have a date aside from the year.