When is the metal on Earth exhausted?

The timing of human depletion of metals is controversial because it depends on many factors such as the ability to mine at great depths and recycle.

Humans are extracting and using minerals faster than they can recover. Photo: Christoph Schaarschmidt

Geological processes take thousands, even millions of years, to create mineral deposits. However, humans extract and use minerals faster than they can recover. According to some estimates, although controversial, the supply of some metals could run out in less than 50 years, IFL Science reported on August 16.

Iron is the fourth most abundant element in the Earth's crust, although much of it is still deep underground and only a small part is accessible as iron ore. In 2022, experts estimate, the Earth contains about 180 billion tons of crude iron ore, with a total content of about 85 billion tons. As plentiful as they may sound, they won't last forever.

Iron ore could run out by 2062, American environmental analyst Lester Brown writes in his book Plan B 3.0: Mobilizing to Save Civilization published in 2008. He also argues that other important mineral supplies such as Lead and copper could be depleted in the coming decades.

"Assuming annual mining growth of 2%, according to USGS data on economically recoverable reserves, the world has enough lead reserves for 17 years, 19 years for tin, 25 years for copper, 54 years for iron ore and 68 years for bauxite (an aluminum ore)," Brown wrote.

However, this statement caused a lot of controversy. Other studies have shown that the potential for metal depletion is significantly smaller than Brown's estimate. In addition, humans can recycle iron and related materials such as steel, meaning that reserves in the Earth's crust are not all.

The main metal at risk of being completely depleted in the next 100 years is copper, according to research by Theo Henckens, an expert at the University of Utrecht, to be published in Science Direct in 2021. Six other minerals are likely to be depleted . for about 100 - 200 years are antimony, gold, boron, silver, bismuth and molybdenum. In addition, 9 minerals that can be depleted in 200-1000 years are indium, chromium, zinc, nickel, tungsten, tin, rhenium, selenium and cadmium.

Other scientists say mineral depletion is not a big concern. Some believe that humans have only scratched the surface of Earth's mineral supply. Most mined deposits are found at depths of only 300 m in the Earth's crust, but they can still be located much deeper.

As technology continues to advance, it is possible that humans will tap into these deep reserves. However, the question is whether it is possible to exploit them without harming the planet or people themselves.

"Do not confuse mineral resources that exist within the Earth with reserves - the portion of mineral resources that have been identified, quantified, and economically extractable. Some studies predict shortages. based on reserve statistics, that is, a very small fraction of the total resources that exist," said Lluis Fontboté, professor in the Department of Earth Sciences at the University of Geneva. He also said that the real problem here is not resource depletion but the environmental and social impact of mining activities.