Copper
Also: Cu, Cuprum, Red metal
Copper (Cu, atomic number 29) is a reddish transition metal with outstanding electrical and thermal conductivity. Regarded as the first metal humans deliberately worked, it is today an indispensable industrial commodity.
Copper is among humanity's oldest working metals: more than 10,000 years ago it was already being cold-hammered in Anatolia and Mesopotamia, and alloying it with tin ushered in the Bronze Age. Today copper is a global bellwether for the economic cycle and industrial development — traders like to call it "Dr. Copper" because the copper price often flags cyclical turning points early. You can find the current copper price and historical price trends on the relevant overview pages.
Properties and occurrence
Copper is a soft, ductile metal with a characteristic reddish colour. Its most important physical features:
| Property | Value |
|---|---|
| Density | 8.96 g/cm³ |
| Melting point | 1,085 °C |
| Electrical conductivity | 58.1 MS/m |
| Thermal conductivity | 401 W/(m·K) |
| Mohs hardness | 3.0 |
Only silver conducts electricity better than copper — at a fraction of the cost. This property makes it the preferred material for cables, windings and electronic components worldwide.
Copper occurs both natively (as the pure metal in nature) and in numerous ores. The most important copper ores are chalcopyrite (CuFeS₂), malachite (Cu₂(CO₃)(OH)₂) and bornite (Cu₅FeS₄). Chile is by far the world's largest producer, mining roughly 25–28 % of the global annual quantity on its own.
Extraction and processing
Primary extraction is predominantly by open-pit mining. The mined ore passes through several processing stages:
- Flotation — enrichment of the copper ore to 25–35 % Cu content (concentrate)
- Smelting and converting — production of blister copper (~98–99 % Cu)
- Electrolytic refining — purification to electrolytic copper (≥ 99.99 % Cu, cathode)
The formula for the copper content of the ore (ore grade) is:
Ore grade (%) = (mass of Cu in ore / total ore mass) × 100
Modern copper mines often work with grades of just 0.5–1.5 % Cu; economic minimum grades sit at around 0.3–0.5 % depending on the project.
Important alloys
Copper is one of metallurgy's most widely used alloying partners:
| Alloy | Composition | Properties |
|---|---|---|
| Bronze | Cu + Sn (tin) | hard, corrosion-resistant |
| Brass | Cu + Zn (zinc) | machinable, decorative |
| Gunmetal | Cu + Sn + Zn + Pb | pressure-tight, for fittings |
| Nickel silver | Cu + Ni + Zn | silver-like, corrosion-resistant |
| Tombac | Cu + Zn (10–20 %) | gold-coloured, for medals |
Copper also plays a central role in precious-metals processing: in 585 gold (14 carat) and red gold, copper is the key alloying partner that determines strength and colour.
Uses and markets
About 65 % of global copper consumption goes to the electrical industry — from power cables and transformers through to electric motors. Other significant consumer sectors include:
- Construction (water pipes, roofing, heating pipes)
- Mechanical engineering and automotive (radiators, brake lines, wiring harnesses)
- Renewable energy (wind turbines and photovoltaic installations need considerably more copper than conventional power plants)
- Electronics and telecommunications (printed circuit boards, semiconductor bonding)
Rising demand from electric mobility and the energy transition is regarded as a structural demand driver: an electric car contains on average three to four times as much copper as a combustion vehicle.
Copper as a traded commodity
The global copper price is set chiefly on the London Metal Exchange (LME) and the COMEX in New York, quoted in US dollars per tonne. Common trading units are:
- LME lots: 25 tonnes (standard contract)
- Cathodes, granules, wire in the physical trade
As an industrial metal — and thus not a precious metal in the narrow sense — copper attracts the standard Irish VAT rate of 23 % on purchase. Its price development depends heavily on global business cycles, China's construction sector and the pace of energy-infrastructure expansion. The exchange-rate tool can retrieve current USD/EUR rates relevant for price conversion.
Note: this article does not constitute investment or tax advice.
Recycling
Copper can be recycled almost indefinitely with no loss of quality. Around 35 % of the world's copper demand is already met by secondary copper (recycling). So-called urban mining — recovery from electronic scrap, old cables and fittings — is growing in importance as ore grades fall and extraction costs rise.
In brief
Copper links past and future like almost no other metal: as the material of humanity's first metalworking and, at the same time, a key raw material for electrification and the energy transition, it remains an indispensable substance. Economists regard the copper price as a reliable leading indicator for global economic development.