The symbol that quite literally stands, more than any other, for freedom and refuge stands in New York Harbor: the Statue of Liberty. Imagining Lady Liberty immediately creates a mental picture: her massive 305-foot stature; her majestic crown and torch; her bluish-green color. However, it turns out that she was not designed to be green, nor was she always that color.The Statue of Liberty was given to the United States in 1885 as a gift from the people of France. She was built over several years out of the decidedly non-green material copper (over 30 tons of it!). So how did she become green?
It has nothing to do with paint (or jealousy). The statue’s green color comes from several chemical reactions. The American Chemical Society made a video breaking down each stage of the statue’s chemical transformation. It turns out that the Statue of Liberty actually has been multiple colors.
As the name of the material would suggest, the statue was originally a
bright copper color. However, once she was assembled in New York
harbor, a reaction called oxidation—which is also responsible for rust—
began. Her copper exterior began to react with the oxygen in the air.
That reaction created tenorite, a dark brown-black material. So her
copper color got darker before it got lighter.
Completing the chemical makeover, sulfuric acid in
the air (much of which comes from New York air
pollution) reacted with the tenorite and the
oxidized copper, turning the exterior green. By 1906,
all traces of copper were gone and the statue was
the color we know today. However, in the early 1900s,
Congress collected money for repairs, suggesting
that the statue be painted its original copper color—