Known since prehistoric times, copper has remained in use longer than any other metal.
With a history of 600 years in applications based in its unique property combination: easily processed: anti-corrosion and suitable for forming alloys and has good conduction property.

It’s the only coloured common metal: red in its pure state, meanwhile its alloys range from white (nickle silver and nickle copper) to gold yellow. Copper is characterised by a face centred cubic crystal. Its pure state is native copper, but is better known under the guise of various metals such as sulphur and basic carbonates.

The element appears as badly formed crystals or threadlike masses and specially coloured tree like shapes. The principal deposits of native copper, important for metal production, are to be found in the United Status, Bolivia, Chile, Russia and Zaire. Its manufacture precedes various steps before the metal separates from the minerals, which are concentrated floating in cells with a capacity of 28 cm3, in such a way as to reach a metal tenor between 25%-35%.
Its extraction is carried out by the “dry state” method using the following processes:
Partial air calcinations obtain a mixture of oxides and sulphurs
of Cu y Fe.
Melting oxidant from the mixture in the presence of silicon and carbon obtaining the metalina(mixture of sulphur of Cu univalent and sulphur of Fe).
Melting of the metalina in the presence of silicon in the Bessemer converter, transformed to sulphur of Cu in oxide.
Reduction in mentioned oxides to produce metal.
One is advised that the different types of copper are hard to work with because they are soft and clog up the tool, they don’t adapt to the welding process, one of the reasons for its raised conductivity and why they easily submitted to gaseous reactions. Copper may be used in braze welding.

The majority of copper products are available in a strained form or forged.

Melting temperature
1083 °C
Boiling point
2595 °C
Specific Heat
0.092 cal\(g °C)
Latent heat of melting
205 J\g
Thermal conductivity
0.94 cal\(cm² °C)
Electrical resistance (from 20°C)
1.7241×10-8 Ohm m
8.90 g\cm
Flexural modulus of elasticity
Variation in volume by melting
4% circa
Coefficient of linear thermal expansion
In normal atmosphere and water, the resistance is good, thanks to a superficial film of oxide which protects the material. The metal is attacked by alkaline products, except nitric acid y hydrogen chloride which dissolve it quickly. Additions of alloys (boro, lithium, cadmium) reduce the oxidation speed at environmental temperature and at higher temperatures with the development of film protectors, however they reduce the conductivity and ease of processing, increasing the mechanical resistance.
More than 50% of all copper is used for electrical purposes. The mentioned property is reduced for cold processing as well as for the addition of alloys: generally an increase in the mechanical resistance causes a reduction in the conductivity (for example, the addition of 1% of cadmium reduces the conductivity by 5%). Impurities represent a damaging factor for conductivity, which introduce problems in operating conditions, for this reason it’s necessary to control these when used for electrical applications.
Recycled copper conserves the same chemical-physical characteristics as the original. For this reason, in Italy, 40% of semi finished copper and alloys are obtained by recycling scrap metal.