hi! you may be interested in some previous posts
Many of us have heard the anecdote that the Statue of Liberty's exterior is actually untreated copper, which developed a layer of the green patina over time. Did the designers of the monument intend this effect?
Why would they make the Statue of Liberty out of copper if they knew it would turn green?
and, out of interest, a few old pictures
Was the Statue of Liberty ever assembled before verdigris set in?
what is the earliest colored photo of the statue of liberty