Copper: Properties, Facts and Photos

What is Copper?

Copper is a reddish-brown chemical element. It was the first metal to be used by humans and the first to be smelted. Smelting is the process of extracting a metal from an ore by heating and melting.

The history of copper can be traced back at least 10,000 years. Imported by the Roman Empire from Cyprus, it was originally called 'aes cyprium', meaning 'metal of Cyprus.' The name was later shortened to 'cuprum.'

Copper is widely used in industry because it resists corrosion from air, moisture and seawater. It conducts electricity and heat and is used in pipes, wiring, heating and cooling applications and cooking pans. 

Copper is often alloyed with other metals, including brass, which is copper and zinc. Bronze is primarily copper and tin, although other elements are often added.

Sterling silver is 92.5% pure silver and 7.5% copper. Even though copper is used as an alloy to strengthen silver, it's quite a soft metal. With it being ductile and malleable, it hardens after being shaped and hammered. When heated, it can be softened again. 

Although pure silver can tarnish, sterling silver tarnishes more easily because the copper accelerates the process.

Copper is an important trace element vital for the health of all living organisms. It can be found in a wide range of foods.

As well as occurring in chemical compounds, copper also occurs as a native element. Known as native copper, this means it occurs naturally in its pure metallic state without needing to be refined or processed.

Native elements are minerals formed from a single chemical element. Gold, sulphur and carbon are all native elements.

Native copper is typically found as irregularly shaped masses or dendritic crystals in copper-rich ore deposits.

The copper we're used to seeing is typically extracted from copper sulphide or oxide ores. Sulphide ores are usually smelted and refined by electrolysis, while oxide ores are generally treated using a chemical solution.

The main difference between native copper and commercial copper is how it occurs and how it's produced. Native copper occurs naturally in metallic form, while commercial copper is extracted from ores and refined to a very high purity. 

Native copper can be used directly without any refining, whereas the other must be processed to remove impurities before it can be used.

In terms of appearance, freshly exposed native copper and commercial copper both have a reddish colour and metallic lustre. Native copper often appears darker because its surface has oxidised.

By 8000 BC, native copper was being used instead of stone. Copper began being alloyed with tin to produce bronze in ancient Egypt around 2500 BC.

Most copper is extracted from ores. An ore is a rock or mineral that contains important elements and metals in sufficient quantities to make extraction worthwhile. However, the amount present is often very small.

Malachite is the oldest ore of copper. Today, chalcopyrite is the most abundant ore of copper.



The Keweenaw Peninsula of Michigan has one of the world's largest concentrations of native copper.

Before September 1992, 1p and 2p coins in the United Kingdom contained 97% copper. This meant the 2p coin contained 6.9 grams of copper and the penny 3.45 grams. As metal prices increased, the composition was changed. Since September 1992, 1p and 2p coins have been manufactured from steel with only a thin copper plating. In 2006, rising copper prices meant that the metal in the older bronze coins became worth more than their face value.

Article Pictures

The copper in our first photo is courtesy of Stan Celestian. The second photo, by Stone Mania, was taken at the Harvard Museum of Natural History in Massachusetts.

The last photo is chalcopyrite, courtesy of Ron Wolf.

Pop-up photos
Sulphur: Courtesy of Géry Parent. Native copper, malachite: Courtesy of Stan Celestian. 

The photos in our article and the links for the pop-up photos link to the original image on Flickr. You may only be able to view them if you join. Joining Flickr is free, with no additional charges.