Samarium: The Audiophile Rare Earth?

Given that we common folk usually encounter it in our consumer electronic gear – especially hi-fi, does samarium represent the audiophile side of the rare earth elements? 

By: Ringo Bones 

More famously known in those ultra-small yet very powerful samarium-cobalt permanent magnets, the rare earth element samarium’s “global strategic importance” seems to be just way greater to be left to geopolitical tensions give that if Beijing blocks supplies destined to the rest of the planet, it would be us civilians – especially the audiophile community – that would be left high and dry. Given its importance in our modern way of life, it would only be proper to know a bit more about this largely obscure member of the rare earth kingdom. 

Discovered by Lecoq de Boisbaudran in 1879 and further chemically refined to be identified to be a member of the rare earth family by Carl Auer von Welsbach back in 1885, the rare earth element samarium’s contribution to human civilization would not be fully realized until almost 90 years after its discovery. The primary source of the rare earth element samarium is the mineral samarskite – which is named after a 19^th Century Russian mining officer, Colonel V.E. Samarsky. 

During the American science boom of the 1960s, samarium was often experimented in laser applications. Calcium chloride crystals doped with samarium have been employed in laser devices for producing beams of light intense enough to burn metal or bounce off the moon. Its more widespread applications in the civilian consumer electronics market now includes those small but powerful samarium-cobalt magnets used in hi-fi headphone units and the small electric motors used in almost everything from disc drives in CD and DVD players and the memory drives and cooling fans in personal computers and laptops. Samarium-cobalt magnets are also extensively used in the actuators of unmanned drones. As a scientific curiosity, the isotope samarium-152 is the only alpha particle emitting radioactive element known to occur naturally among the elements lighter than bismuth. Samarium-152 has a half-life of 1-trillion years. 

Cerium: The Most Abundant Rare Earth Element?

Though considered “rare” in name only but does cerium qualify as the most abundant rare earth element?

By: Ringo Bones

It is considered rare in name only given that cerium occurs in the Earth’s crust at a concentration of 44 parts per million. On a percentage basis of abundance in the Earth’s crust – cerium is more plentiful than either tin or lead. And cerium is also found dissolved in seawater at a concentration of 1.8 tons per cubic mile of seawater. By comparison, the rare earth element thulium – the scarcest of the family on a percentage basis in the Earth’s crust – is only slightly rarer than iodine.

Chemical symbol Ce, atomic number 58 and named after the asteroid Ceres, cerium was discovered in 1803 by Jöns Jakob Berzelius and Wilhelm Hisinger of Sweden. It is the chief ingredient – at just under 50 percent – of misch-metal alloy often used in the manufacture of lighter flints. Cerium is used in alloys to make heat-resistant jet engine parts; its oxide has been used as a de rigueur petroleum cracking catalyst since the 1960sand as a volumetric oxidizing agent in most important industrial chemical processes. 

Rare Earth Hexaborides For Cathode Poisoning Resistant CRTs?

Even though they are a fairly dated discovery, are rare earth based hexaboride cathode coatings made possible ultra-long-life cathode ray tubes in color television sets and even hi-fi thermionic vacuum tubes?  

By: Ringo Bones 

Though now virtually forgotten when virtually every consumer electronic devices we have are solid state based – including the now “affordable” organic light emitting diode (OLED) video display monitors, there was a time when cathode poisoning was of grave concern – like back in the days when the first programmable digital computers still use thermionic vacuum tubes. But as thermionic vacuum tubes returned in the high end audiophile scene, and given there are certain cathode ray tube based color television sets manufactured in the mid 1990s that are still running, could the concept of cathode poisoning – in a strange twist of fate – inspire consumer electronic companies to design longer lasting thermionic vacuum tubes, even ones rivaling the longevity of solid state transistors and integrated circuits? 

Back in the 1950s, when vacuum tube technicians were still concerned with their tubes developing “sleeping sickness” whenever it was kept in soft-start mode for a prolonged period of time in radar and digital computer applications, cathode poisoning was of a grave concern on how to prolong the life of their banks upon banks of vacuum tubes when they are mostly switched to low current mode in switching applications. In short, cathode poisoning is the failure mode of a thermionic vacuum tube where the emissive layers degrade slowly with time and much more quickly when the cathode is overloaded with too high a current – which usually results in weakened emission and diminished power of the vacuum tubes or brightness of the cathode ray tubes – i.e. CRTs. Given what every “thermionic vacuum tube experts” had learned through such first hand events, were there any progress made in prolonging vacuum tube life and making cathode poisoning less of a concern? 

Various rare earth borides had been used to prolong the life of thermionic vacuum tubes but there’s no news yet on how they affect sound quality of vacuum tubes when used in audio applications. Like boride cathode vacuum tubes that use lanthanum hexaboride and cerium hexaboride as coating of some high-current cathodes. Hexaborides show low work function around 2.5 eV. They are also resistant to cathode poisoning. Cerium hexaboride cathodes show low evaporation rate at 1,700 Kelvin than lanthanum hexaboride, but becomes equal at 8,800 Kelvin and higher. Cerium hexaboride cathodes have one and one half times the lifetime of lanthanum hexaboride cathodes due to its higher resistance to carbon contamination. Hexaboride cathodes are about 10 times as bright as the tungsten ones and have lifetimes up to 10 to 15 times longer. They are used in electron microscopes, microwave vacuum tubes, electron lithography, electron beam welding, X-Ray vacuum tubes and free electron lasers. However, these materials tend to be expensive. Other useful rare earth based hexabordes with long lives are yttrium hexaboride, gadolinium hexaboride and samarium hexaboride. 

Even though rare earth based hexaboride cathode coatings for thermionic vacuum tube devices may not yet be a hit in the hi-fi audio world sound quality wise, but I think these might have contributed in making extra long life CRTs or cathode ray tubes in television sets. Back in 1995, I’ve bought a 14-inch Goldstar color TV manufactured by LG Collins Electronics Manila, Inc. It’s a model CN-14A146 with serial number 60524212 which I bought for around 150 US dollars and it is still running until this very day. I wonder if this particular Goldstar 14-inch color TV uses a rare earth based hexaboride cathode coated CRT? 

The James Webb Space Telescope: A Rare Earth Telescope?

Slated to replace the now aging Hubble Space Telescope, is the James Webb Telescope deserve the moniker “Rare Earth Telescope” due to the amount of rare earth elements needed to make it do its cosmic exploration?

By: Ringo Bones 

Insiders from Lockheed Martin often joked that its rare earth element content equals that of three Predator drones, but why does the James Webb Space Telescope need such prodigious amounts of rare earth elements to do its intended function in exploring the cosmos? Well, maybe it has to do on where the new space telescope will be finally situated. 

Unlike the Hubble Space Telescope, which is situated in low Earth orbit 250 miles or 400 kilometers above us, the James Webb Space Telescope will be situated 1-million miles from the Earth so any fixing by NASA astronauts in case of a post launch in-space field repairs will be much, much harder than the Hubble fix in low Earth orbit by EVAing astronauts back in the early 1990s. The unfurling of the James Webb Space Telescope’s over-sized mirrors and heat shield 1 million miles in space must go as planned or it will become a sad multi-billion US dollar astronomical blunder. 

In order for the James Webb Space Telescope to achieve reliability in the hostile vacuum and near absolute zero cold of outer space, its servo motors are especially made with advanced proprietary samarium rare earth magnets that can still reliably function at 2.7 Kelvin – the average temperature of the hard vacuum of outer space. These servo motors not only unfurl the over-sized mirrors once the space telescopes arrive in a point in space 1-million miles away from Earth but also the aluminized gold plated mylar heat shield that would protect the James Webb Space Telescope’s main mirror from the relentless unfiltered glare of the Sun. 

Minami Torishima Island: Japan’s Latest Geopolitically Contentious Rare Earth Metals Strike?

In an attempt to wean the country’s over-dependence on Mainland China for rare earth needs, is Japan’s latest rare earth strike on the Minami Torishima Island too geopolitically contentious?

By: Ringo Bones

From recycling obsolete consumer electronic equipment to prospecting the seabed of the country’s territorial waters, Japan has for the past few years seems to be in a mad dash to wean itself from the People’s Republic of China when it comes to meeting its rare earth metal needs. But is the latest find on Minami Torishima Island might just too geopolitically contentious for Japan and other countries desperate to get its rare earth metal needs other than Mainland China?

Upon hearing sketchy reports of Japanese rare earth explorations of the Minami Torishima Island – also known as Marcus Islands – via CB radio “DX-ing” a few days ago, it seems like Minami Torishima Island is a place forgotten by Google search because the “instant search results feature” of the famed search engine can’t even redirect “confused online researchers” who don’t know how to spell the said Japanese in its accepted Roman letter spelling who are just recently looking for facts about Minami Torishima Island.

Even on the entry on Wikipedia, the island seems to be a 21^st Century geographical obscurity in itself. Minami Torishima Island also known as Marcus Island is located 1,848 kilometers South-East of Tokyo – quite veritably for all intents and purposes in international waters in the middle of the Pacific Ocean. And as of late, the island is claimed by two East-Asian regional superpowers – namely Japan and The People’s Republic of China. And anytime soon, either the island’s native inhabitants or some other countries would be voicing their sovereignty on the contentious island, making the situation akin to a real-life version of the TV series Last Resort.

The latest exploratory results of a Japanese rare earth metals mining firm on the said island have shown that the seabed surrounding the island contains commercially viable deposits of dysprosium – a rare earth metal vitally important for the manufacture of tiny, powerful magnets for use in motors of modern computer main memory drives and other indispensible contemporary hi-tech applications. But will Japan’s bid to wean itself form Mainland Chinese sourced rare-earth metals creates more regional geopolitical harm than good?

Even if Japan will win an internationally recognized claim on the Minami Torishima Island – otherwise known as the Marcus Island – it will only be just a first of the very difficult hurdles that it will overcome in extracting the economically viable deposits of dysprosium in the island’s seabed. First of all, the economically viable dysprosium ore – literally beige colored mud ooze – on the island’s seabed lies on average 3,000 to 5,000 meters below the Pacific Ocean. And given that there’s this 1970 UN General Assembly declaration that deep-sea minerals were the common heritage of mankind, Japan could end up sharing some of the profits with the Beijing government, and with a preexisting dispute with the People’s Republic of China over the Senkaku Islands, this situation could get ugly fast.

International law rigmaroles aside, Japan’s rare earth metals mining operations on the Minami Torishima Island – if it ever gets the green light – could and might soon attract ship-borne environmental picketing from the world’s leading environmental pressure groups like Greenpeace. This scenario has a high probability of certainty because every commercially viable rare earth metal ores that have been currently so far tend to be weakly to strongly radioactive due to the fact that that rare earth metals’ actinide homologues - like thorium and uranium - also occurs naturally in these ores, which is the main reason why mine tailings of rare earth metal mining and refining facilities can be significantly radioactive – at levels that can certainly pose a clear and present health risk to humans who come close to it.             

German Rare Earth Metals Recycling Program: Now Economically Viable?

Though still developed by an “East-German born” chemist, will Germany’s rare earth metals recycling program eventually reach economic viability?

By: Ringo Bones

Thanks to The People’s Republic of China’s “stranglehold” on the global commercial rare earth metals supply, some in the affluent industrialized West are already contemplating novel ways to develop an alternative method of acquiring their quotas of rare earth metals. Had anyone already checked their used and busted compact fluorescent bulb pile for rare earth metals?

German chemist Wolfram Palitzsch has during the past few years been developing an economically viable method to extract rare earth metals from used and/or busted compact fluorescent bulbs that as for now been just thrown away. Somewhat appalled by the sight of garbage-bags full of phosphors being thrown by German factories, Palitzsch was compelled to find a way to recover the increasingly precious rare earth metals from just winding up in a communal landfill.

At present and using his own proprietary methods, Palitzsch successfully developed a chemical extraction method for europium – a rare earth metal commonly used as component for red phosphors in color TV sets – from the white powder phosphors from used compact fluorescent bulbs. Even though his method worked, it can’t still be yet classified as an economically viable method to extract rare earth metals from busted compact fluorescent bulbs – compared to mining rare earths directly from the Earth’s crust - because different brands and models of compact fluorescent bulbs require somewhat different chemical extraction methods to recycle the rare earth metals – making a cost-competitive one-size-fits-all chemical process the next step for him to develop.

But after the environmental protests of low-level radioactive residues in some rare earth metal mines and processing mines not located in Mainland China – like the Australian owned Lynas rare earth metal mine and processing plant in Kuantan, Malaysia – recycling rare earth metals from “urban wastes” like phosphors from used compact fluorescent bulbs might only be the best long-term solution for the current rare earth metals shortage. Primarily it is a contentious political issue, but most people think that recycling rare earth metals from their own industrial and urban wastes – instead of buying it from a relatively despotic nation-state like The People’s Republic of China – might give the rest of us a cleaner conscience when it comes to corporate social responsibility.

When he was growing up in then communist East Germany, chemist Wolfram Palitzsch got first-hand lessons on recycling and resource conservation from his father because at that time, anything in the supposed resource Utopia of the then socialist East Germany might suddenly be in short supply. Palitzsch watched his father recycle bottle tops for latter use in handy do-it-yourself repairs and the rest to be sold in the local scrap-yard for a bit of extra cash and to barter for other goods. Palitzsch’s method of chemically extracting rare earth metals, as in europium extraction, from busted fluorescent bulbs is an offshoot from a chemical process he previously developed in extracting indium – an increasingly expensive and rare metal – from used solar photovoltaic cells. Ironically, he named the firm that he founded for extracting valuable elements from industrial and urban wastes “Loser Chemie” even though someday it might be a winner when it comes to extracting rare and precious elements from urban and industrial wastes.   

The Rare Earth Metals Industry Versus Mother Nature

Is it really worth compromising established environmental laws in the name of easier rare earth metal access for the whole world?

By: Ringo Bones

Thanks to The People’s Republic of China’s strategic stranglehold of the global rare earth metals supply, countries denied easy access to rare earths could resort to disregarding established legal precedents protecting the environment. A case in point is the latest courtroom battle between the Australian owned Lynas Rare Earth Plant and the local political constituency and environmentalist of Kuantan, Malaysia.  As the local court is on an ongoing negotiation to whether allow Lynas a permanent application to run the plant, environmental concerns cast a long shadow over the proceedings given that a similar rare earth metals processing plant located near the place was closed down 18 years ago for failure to comply with preexisting environmental laws. 

Given that The People’s republic of China controls about 97% of the global rare earth metals mining and processing, any country with a beef with the Beijing government – either on the issue of Tibet, human rights or unfair international trade practices – has no other choice but to put ethics in second place over access to the coveted rare earth metals commodities. But will restarting rare earth metals mining and processing facilities elsewhere in the world even though they don’t quite pass muster the rather stringent local environmental laws be a better option?

Even though Malaysia’s Lynas Rare Earth Plant is the biggest rare earth metals processing and refining facility outside of Mainland China, its operation has been more or less on hold since May 2012 due to environmental concerns voiced by local environmental activists and the local inhabitants of Kuantan - by the way, Kuantan is the capital of Pahang, Malaysia's third largest state. Both locals and environmentalists are currently picketing the plant due to concerns over lack of oversight when it comes to the safe disposal of the low-level radioactive wastes which are a by-product of rare earth metal purification and processing. The thorium and radon gas content of the overburden in a typical rare earth metals processing plant has a radioactivity level sufficient enough to increase the likelihood of cancer on any persons exposed to it for a prolonged period of time. Will more stringent disposal of low-level radioactive wastes still make the rare earth metals produced by the Malaysian Lynas plant be still cost-competitive compared to ones made by Mainland China?