Part 1: What are metals?

Eighty percent of all chemical elements are metal

Let's start with a very basic question: What are metals, exactly? The simplest answer is: Metals constitute a rather large group of chemical elements. Metals make up around 80 percent of all chemical elements in the periodic table. There is no clear-cut boundary between metals and non-metals. In other words, there is no sharp dividing line that can be drawn between them. This means that there is a whole series of semi-metals in the metal to non-metal crossover area. These are chemical elements with both metallic and non-metallic properties.

Production of major metals and plastics in 2021 (in million tons per year)

Metals from an industrial perspective


With a share of more than 90 percent, iron is the metal that is most processed worldwide. Iron is the main component of steel. Steel is an alloy made from iron and carbon and, thanks to its strength and toughness, is an enormously versatile material with around 3,500 different grades. Whether it's mechanical engineering, vehicle construction, the electrical industry, shipbuilding, or when used in conjunction with concrete, steel can be found practically everywhere. According to the World Steel Association, more than 1.9 billion tons of steel in total were produced in 2021. The most significant steel-producing country is the People's Republic of China, where more than one billion tons of steel were produced in 2021 alone.


The second most important metal from an industrial point of view is aluminum. Although aluminum is the third most common element in the world, bauxite is the only raw material that can be processed industrially. Aluminum is more expensive than iron or steel, but for that it weighs less. For this reason, aluminum is used predominantly when designs that are more lightweight are required – for example in the aerospace industry. Aluminum also has a permanent place in the packaging industry, for instance in the manufacture of cans or coating of packaging material. Global aluminum production totaled around 102 million tons in 2021. China also tops the list of aluminum-producing countries.


In third place is copper. This is a metal characterized in particular by its good electrical conductivity. That is why around 70% of copper is used for power transmission applications. Copper power lines are found wherever current flows: whether it's in cables or on printed circuit boards, coils in electric motors, or in transformers. The construction industry also needs copper, for example for pipes or cladding. A total of 28 million tons of copper were produced globally in 2021. Incidentally, the world's biggest copper-producing country is Chile, followed by Peru.

Next part: Why metals have to turn green

Metals are therefore indispensable for humankind. Their significance is also reflected in the fact that their names bear testament to whole periods of human history, such as the Bronze Age or the Iron Age. However, the production of metals accounts for around 10 percent of global greenhouse gas emissions, which contributes significantly to global warming. We'll take a look at why that's the case in the next part of our series.