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 oldest metal deliberately used by humans and today an indispensable industrial raw material.
Copper is one of humanity's oldest useful metals: more than 10,000 years ago it was cold-hammered in Anatolia and Mesopotamia, and its alloy with tin ushered in the Bronze Age. Today copper is a global leading indicator for the economy and industrial development - traders like to speak of "Dr. Copper" because the copper price often signals economic turning points early. You can find the current copper price and historical price developments on the corresponding 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 electric current 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 native (as 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 around 25-28 % of the global annual quantity alone.
Extraction and Processing
Primary extraction takes place predominantly in 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 in ore (ore grade) is:
Ore grade (%) = (mass of Cu in ore / total mass of ore) × 100
Modern copper mines work with ore grades of often only 0.5-1.5 % Cu; economic minimum grades lie, depending on the project, at around 0.3-0.5 %.
Important Alloys
Copper is one of the most widely used alloying partners in metallurgy:
| Alloy | Composition | Properties |
|---|---|---|
| Bronze | Cu + Sn (tin) | hard, corrosion-resistant |
| Brass | Cu + Zn (zinc) | good machinability, 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 metal processing: in 585 gold (14 carat) and in red gold, copper is the most important alloying partner determining strength and colour.
Use and Markets
About 65 % of global copper consumption goes to the electrical industry - from power cables through transformers to electric motors. Further significant buyer sectors are:
- Construction (water pipes, roofing, heating pipes)
- Mechanical engineering and automotive (radiators, brake lines, wiring harnesses)
- Renewable energies (wind turbines and photovoltaic installations need considerably more copper than conventional power plants)
- Electronics and telecommunications (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 primarily traded on the London Metal Exchange (LME) and on 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 physical trading
As an industrial metal - and thus not a precious metal in the narrower sense - copper is subject to the standard VAT rate on purchase in Malta (18 % Maltese standard rate). Its price development depends strongly on global economic cycles, the Chinese construction sector and the pace of expansion of energy infrastructure. At the exchange rates page you can retrieve current USD/EUR rates that are relevant for price conversion.
Note: This article does not constitute investment or tax advice.
Recycling
Copper is almost infinitely recyclable without loss of quality. Around 35 % of global copper demand is already met by secondary copper (recycling). So-called urban mining - recovery from electronic scrap, old cables and fittings - is gaining increasing importance in view of falling ore grades and rising extraction costs.
In Brief
Copper connects history and future like almost no other metal: as the material of the first human metalworking and at the same time as a key raw material for electrification and the energy transition, it remains an indispensable material. Economists regard the copper price as a reliable early indicator of global economic development.