Speaker 1: Welcome to Brainstuff, a production of iHeartRadio. Hey Brainstuff Lauren
Speaker 1: vogelbamb Here. On Christmas Eve in the year eighteen hundred,
Speaker 1: English scientist William Hyde Wallaston and his colleagues Smithson Tenant
Speaker 1: unwrapped a gift to themselves. It was a piece of
Speaker 1: nearly pure platinum ore, secretly purchased and smuggled from the
Speaker 1: Spanish colony of Duevo Granada in South America. Oh, what's
Speaker 1: Columbia today? The price tag was seven hundred and ninety
Speaker 1: five pounds worth, a little over one thousand American dollars
Speaker 1: at the time and over twenty three thousand dollars today.
Speaker 1: The pair had high hopes for this hunk of rock.
Speaker 1: A Wallaston believed he could create a new chemical process
Speaker 1: that would make the solid ore a malleable platinum. Little
Speaker 1: did Walston know that his Christmas ore was the gift
Speaker 1: that would keep on giving. Their sample had secrets of
Speaker 1: its own, hidden away, a new, rare elemental metal never
Speaker 1: known to science before then. Today it's one of the
Speaker 1: most valuable and precious metals on the planet Rhodium. With
Speaker 1: his chunk of smuggled platinum ore, in a few years
Speaker 1: Wallaston did what earlier scientists could not. He achieved a
Speaker 1: chemical process that isolated platinum and rendered it malleable. As
Speaker 1: he dissolved the platinum ore in his backyard garden laboratory,
Speaker 1: he produced both a soluble and a non soluble residue.
Speaker 1: After precipitating the soluble solution, he noticed reddish salts remained.
Speaker 1: Red salts are not typical of platinum, and Walaston suspected
Speaker 1: something else was present in the sample. Over eighteen oh
Speaker 1: three and eighteen oh four, Walaston announced that with the
Speaker 1: sample of platinum ore, he had discovered two other precious metals.
Speaker 1: One he called polydium and the other rhodium, and the
Speaker 1: name is rooted in the Greek word for rose. Because
Speaker 1: of those reddish salts, Rodium is now part of what's
Speaker 1: known as the platinum group metals, six metals with similar
Speaker 1: characteristics that are clumped together in the periodic table and
Speaker 1: often in deposits in real life. The group consists of
Speaker 1: rodium and polydium, perhaps obviously platinum, and then ruthenium, iridium,
Speaker 1: and osmium. Platinum group metals are also considered precious metals
Speaker 1: alongside gold and silver, a meaning that they're rare and
Speaker 1: have a high economic value due to a number of traits.
Speaker 1: They're fairly durable, not very reactive, easily workable or ductile,
Speaker 1: and they're shiny. Erodium is an ultra shiny, corrosion resistant
Speaker 1: metal that has become useful in many industries, including the automobile, jewelry, chemical,
Speaker 1: and electrical trades, and that usefulness, combined with its scarcity,
Speaker 1: can keep the price high. Today, the price of rodium
Speaker 1: is four one hundred dollars in ounce. Compare that to
Speaker 1: platinum at nine hundred and sixty two bucks anounced or
Speaker 1: gold at one thousand, nine hundred and seventy two. Only
Speaker 1: iridium is higher at four thousand, six hundred dollars an ounce,
Speaker 1: but in twenty twenty one, rodium was all the way
Speaker 1: up to twenty nine thousand dollars in ounce. The volatile
Speaker 1: and high prices are most likely due to new regulations
Speaker 1: for cleaner emissions in the automobile industry, particularly in China
Speaker 1: and Europe, combined with supply chain issues during the COVID
Speaker 1: nineteen pandemic. When rodium is found, it's never in its
Speaker 1: pure form, or rather it's almost always collected as a
Speaker 1: minuscule byproduct of platinum, copper, or nickel refining. South Africa
Speaker 1: is the largest producer of rodium by way of the
Speaker 1: country's massive platinum mining operations, which have been called into
Speaker 1: frequent question of the last ten years due to labor
Speaker 1: rights and human rights abuses. People have been mining rodium
Speaker 1: as a byproduct platinum since the nineteen thirties after large
Speaker 1: sediments of platinum ore were found in South Africa. Of
Speaker 1: available rodium, eighty percent is used in catalytic converters in
Speaker 1: cars to help clean exhaust emissions. Rodium is uniquely exceptional
Speaker 1: at breaking down nitrous oxide molecules, the brownish, poisonous gas
Speaker 1: given off by fossil fuel powered cars, trucks, boats, power plants,
Speaker 1: and turbines, among many other offenders. Though the impact of
Speaker 1: nitrous oxide emissions cause irreparable damage to our bodies and ozone,
Speaker 1: it would be a lot worse without rodium. It's also
Speaker 1: useful in industrial laboratories as a catalyst for making nitric acid,
Speaker 1: acetic acid, some kinds of silicone, rubber, and menthol the
Speaker 1: minti flavor in chewing gum. Because rodium is resistant to
Speaker 1: corrosion and conducts electrical current easily. It's used as a
Speaker 1: coating for optic fibers and optical mirrors, headlight reflectors, and
Speaker 1: electrical material. However, the average human is most likely to
Speaker 1: directly encounter rodium in shiny, lustrous jewelry. Even though it's
Speaker 1: not the easiest metal to work with, it's extremely hard
Speaker 1: and has a very high melting point at three thousand,
Speaker 1: five hundred and ninety five degrees fahrenheit or two thousand
Speaker 1: and thirty five degrees celsius. Before the article this episode
Speaker 1: is based on How Stuffworks. Spoke with Sean Peterson, supervisor
Speaker 1: of Jewelry Manufacturing, Arts, Research and Development at the Gemological
Speaker 1: Institute of America. He said a rodium by itself is
Speaker 1: too hard for general jewelry making purposes. The most common
Speaker 1: use for rodium is as a plating over other metal alloys,
Speaker 1: either to help protect against allergies or to improve the
Speaker 1: color of the jewelry item. Jewelers seek roodium to use
Speaker 1: in the jewelry making process because it is bright, silvery
Speaker 1: white in color, and very hard, which can help make
Speaker 1: the jewelry more scratch and corrosion resistant. It's also hypo allergenic,
Speaker 1: which can help those that may be allergic to certain
Speaker 1: jewelry metal alloys. The con is that the rhodium plating
Speaker 1: is only a thin layer coating jewelry. This means that
Speaker 1: over time the roodium will reduce due to wear and tear.
Speaker 1: Because you need so little rodium to plate a piece
Speaker 1: of jewelry, it's relatively affordable, though you may have to
Speaker 1: have it replated once every year or two to keep
Speaker 1: its luster up. So keep in mind that the color
Speaker 1: and shine of a rodium plated piece of jewelry will
Speaker 1: change over time without that additional cost and work. Today's
Speaker 1: episode is based on the article roodium is Earth's rarest
Speaker 1: and most expensive precious metal on HowStuffWorks dot Com, written
Speaker 1: by Aleison Trautner. Brains Stuff is production by Heart Radio
Speaker 1: in partnership with how stuffworks dot Com and is produced
Speaker 1: by Tyler Klang. Four more podcasts from my heart Radio,
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