Why is copper used for statues?

Answer 1

Copper is a very durable material when exposed to weather and is soft enough that it can be easily moulded to curved shapes such as those in the Staute of Liberty. It is also traditionally used in buildings for complex roofs, so there would have been tradespeople available trained to use it.

Other metals that can be moulded are: Lead but it does not have the attractive verdigris colour, and gold much is more expensive.

Answer 2

AnswerInitially, bare Cu metal atoms react with air to form the pink oxide, cuprite, Cu2O, which has Cu+1 cations. This gradually oxidizes further to the black oxide, tenorite, CuO, with Cu+2 ions. The black sulfide CuS also sometimes forms. In the presence of moisture, the blackish layer slowly reacts with sulfur dioxide and carbon dioxide from the air to eventually form the patina, which is a mixture of 3 minerals:

brochantite, a green, hydrated copper sulfate, Cu4SO4(OH)6

malachite, the green, hydrated copper carbonate Cu2CO3(OH)2

azurite, the blue, hydrated copper carbonate Cu3(CO3)2(OH)2

In these compounds, copper atoms from the metal surface have been fully oxidized into Cu+2 (cupric) ions. The rate of patina formation and the proportion of the components depend upon humidity and the amount of air pollution. In European cities, where sulfur-containing coal has been burned for centuries, brochantite predominates on older copper roofs and statuary. In rural environments elsewhere, malachite may predominate.

Answer 3

It is made of copper and in the sea air you see the oxidation in it's color of green.

Answer 4

When copper is exposed to oxygen, it oxidizes and turns green - which is why the Statue of Liberty is green.