Of course, when asked what the most expensive metal is, the vast majority would answer that it is gold. Its price is astronomical: today, it costs almost 1,800 euros per ounce (31.1 grams). And yet, Gold is not the most expensive metal in the world, although it is in the top five. The first place on the podium is occupied by a much lesser-known element: rhodium.
It is currently the most expensive precious metal and, at the same time, one of the rarest. Rhodium is priced at $4,100 an ounce at the time of this writing. But just a few months ago, in December 2022, the value was $14,000 an ounce. Anyway, much more than gold
Why is it very expensive? Rhodium does not readily react with oxygen, making it a precious metal and a perfect catalyst, resistant to both corrosion and oxidation. general durability and its high melting point of 1,964 degrees Celsius They assign it to the platinum group metals along with platinum itself, as well as palladium, osmium, iridium, and ruthenium.
Rhodium is notable for its ability to withstand water and air temperatures of up to 600 degrees and to remain insoluble in most acids, making it extremely versatile for use in automotive, aircraft, electrical contacts, and high temperature-resistant thermocouples and cables, according to the science portal IFLS.
Despite its rarity and beauty, statistics from 2019 show that nearly 90 percent of rhodium demand came from the jewelry sector. catalytic converters for cars in the manufacture of catalytic converters, a possibly inglorious use for one of the rarest precious metals on earth.
A very rare metal on earth
It is an extremely rare metal; it occurs at approximately 0.000037 parts per million in the Earth’s crust, while gold occurs at an amount of about 0.0013 parts per million, according to the Royal Society of Chemistry.
Where are the main deposits? This item is mined mainly in South Africa and Russia. However, rhodium is also a by-product of refining copper and nickel ores, which contain up to 0.1 percent of this precious metal. About 16 tons of rhodium are produced annually, with an estimated reserve of 3,000 tons on the planet.
A British chemist named William Hyde Wollaston was responsible for the discovery of this material when he extracted it from a piece of platinum found in South America in 1803. Wollaston himself had recently discovered palladium.
Rhodium, which is normally associated with deposits of platinum, was recovered from the Wollaston sample by removing the platinum and palladium, leaving a dark red powder that was treated with hydrogen gas to reveal the rhodium.
Although the solid metal gleams a bright, reflective silvery white, rhodium takes its name from the Greek “rhodon,” meaning rose, alluding to the red color of rhodium salts
