Copper Ageing Process

With its distinctive red-orange colour and pliable nature, copper is one of the most popular metals for decorative metalwork, lampposts and cookware. Although beautiful, copper is known for its unique aging process when exposed to the air and water, particularly salt water, and it is very important to be aware of this process when purchasing copper items.

The scientific term for copper aging is known as ‘Oxidation’, whereby the oxygen in the air directly reacts with copper elements by attacking the outer layer of the metal work. This means that, without a protective varnish layer, genuine copper will naturally patina over time, eventually turning a green-blue Verdigris colour. A perfect example of copper’s final colourisation stage is the famous Lady Liberty of New York City.

This unique oxidation process doesn’t actually negatively affect the metal in any way other than its colour. In fact, this process prevents further oxygen exposure by strongly bonding to the surface of the copper, helping shield the metal work from any other elements. The below image details how the colour of copper changes over time.

The oxidation process of copper can take a number of years depending on the atmospheric conditions that the item is kept in, generally varying between 2-5 years. Due to the high salt content in sea air, items kept within close proximity to the coast will age a lot faster than those that are not.

If you do not wish for your copper purchase to age to a Verdigris colour, we suggest that you apply a layer of yacht varnish as and when required.