The Statue of Liberty's thin copper skin rests on a flexible framework that allows it to vibrate in the wind, preserving its structure for over 130 years.
Copper skin thickness compared to coins
The copper skin of the Statue of Liberty is less than 2.4 millimeters thick, about the same as two one-cent euro coins stacked together. This thin copper covering, weighing 31 tons, is supported entirely by an internal framework designed by Gustave Eiffel and Maurice Koechlin.Copper's transformation to green patina
The copper skin was originally bright in color, but over time, oxidation caused it to turn green, forming a patina that became visible around 1906. This patina, sometimes over one millimeter thick, protects the statue from wind, salt water, and pollution, and the National Park Service has declined requests to polish it back to its original color.Internal framework's design and construction
The internal framework, designed by Eiffel, consists of a central steel pylon and a secondary network of flexible metal bars that follow the statue's body shape. Built in Paris, the framework supported the statue as it was shaped, hammered, and assembled before being disassembled and transported to New York.Flexible design prevents structural damage
Eiffel's design went against the usual approach by creating a flexible rather than a rigid structure. The flexibility allows the copper skin to vibrate slightly in the wind, distributing forces across the entire structure. This design has prevented major reconstruction since the statue was completed in 1886.Exhibition highlights statue's design
The year 2026 marks the 140th anniversary of the statue's inauguration by President Grover Cleveland. In Paris, the Musée d'Orsay is hosting an exhibition titled Auguste Bartholdi, La Liberté éclairant le monde, which explores the statue's design and construction through a hundred works and a virtual reality tour.
