26 January, 2023

The rise of the world's most expensive natural metal: ten times more than gold

The price of rhodium has multiplied more than 3 000% in this five years. If at the beginning of the year 2017 the kilogram of rhodium was quoted at 21 500 euros

Voice of Diaspora

Technology – Today, rhodium is the most valuable natural metal in the world, with a market price close to half a million euros per kilogram, ten times more expensive than gold and fourteen times more than platinum.

The increase in the demand for rhodium is closely related to the search for efficient and non-polluting technologies.: is the base, for example, from artificial photosynthesis.

But nevertheless, the Earth does not understand markets or remedies, and it doesn't make it easy. Rhodium only exists in very few places on the planet, geologically unique regions, in which billions of years before humans traveled in polluting vehicles the great continental masses broke apart. Through those cracks the rhodium ascended.

The price of rhodium has multiplied more than 3 000% in this five years. If at the beginning of the year 2017 the kilogram of rhodium was quoted at 21 500 euros –then gold surpassed it with a price of 36 000 euros–, reached a historical record of 822 000 euros in april 2021.

The most recent studies foresee that this price escalation will continue in the near future due to the increase in demand for this metal for new technological applications., mainly related to the search for sustainable solutions.

In the world they are consumed around 32 tons of rhodium per year. Industrial recycling of rhodium is possible, and economically viable, but occupies only 9.5 tons. In such a way that the extraction of primary natural sources is still necessary to cover the rest of the demand.

Approximately the 80 % of the world's annual production of rhodium goes to the manufacture of catalytic converters and catalytic converters for low-emission vehicles. In these components incorporated into the exhaust system, rhodium – often together with platinum and palladium – reacts with polluting gases, generating less harmful noble or inert gases. For example, nitrogen oxides (NOₓ) are converted to molecular nitrogen (N₂) and oxygen (O₂); these are harmless gases found naturally in the air we usually breathe.

Rhodium is the basis of the revolutionary technology of artificial photosynthesis. Its ability to catalyze artificial photosynthesis reactions in solar micropanels is much greater than that of other components and allows the transformation of sunlight, water and carbon from the air into hydrogen that can be used as fuel.

The high price of rhodium is not only due to its irreplaceable nature for technology and our limited ability to recycle, but to its scarcity in the earth's crust, where it is found in extremely low concentrations, which rarely exceed 0,001 grams per ton of rock.

This article was originally published on The Conversation. read the original.