Neodymium magnets (also known as NdFeB, NIB, or Neo magnets) are a stupendous alloy of neodymium (Nd), iron (Fe) and boron (B), delivering a huge increase in force over ferrite, samarium cobalt, and ALNICO (aluminum (Al), nickel (Ni) and cobalt (Co)). Neo magnetics have enabled lighter headphones, more compact compression drivers that can more tightly be arrayed, portable DJ speakers that do not cause hernias, and ribbon speakers with extended and smoother response.
Developed independently but simultaneously by Sumitomo and GM (Magnequench) in the early 1980s, and first appearing in an Electro-Voice compression driver soon after, early neodymium had its issues from corrosion to loss of characteristics when the speaker heated up to legal issues with non-licensed Chinese vendors. But in the 1990s, performance improved and it seems that as the process was refined, it was the impurities that were one of the main sources of corrosion so MGO (the magnetic strength measured in megagauss oersteds) went up along with the long-term stability of the magnets. Neodymium became even more enticing as pricing dropped as many Chinese vendors entered the supply chain.
Back in the 1950s and 1960s, Alnico was the most common magnet used in loudspeakers. However, a shortage in materials and increased costs for Alnico during that time precipitated a shift to the widespread use of the ceramic (Ferrite) magnets. In the 1990s, speaker manufacturers started seriously evaluating the potential benefits of using neodymium magnets in loudspeakers. Although neodymium magnets were expensive, they allowed loudspeaker motors to be as little as half the weight of comparable ceramic magnet motors.
Yet, today's transducer designers think long and hard before going with a neodymium design because back in 2011 price fixing resulted in skyrocketing magnet costs. The Chinese government decided to limit and control pricing on Neo magnet exports (while keeping Neo pricing down for domestic consumption). Specifically, export quantities had quotas. The fallout of this was many brands bringing back their ferrite designs. Neo pricing fell dramatically in 2012 and since then pricing has been reasonable, but it has slowly been creeping up.
China is not the only source of rare earth metals such as Neo, in fact the desert area along the border of California and Nevada is full of rare earth metals... Actually, rare earth metals are not so rare here at all with reserves of about 20 million tons in the vicinity of Mountain Pass, CA. You would think there would be a mine... and there is. I pass it every trip I take from the Bay area (Northern California) on my way to CES - you take highway 15 on the way to Las Vegas, NV, and get off on Bailey Road (just before the border to Nevada) and you are right at the mine.
The story is that the Mountain Pass deposit was discovered by a uranium prospector in 1949, who noticed the high radioactivity. Rare earth metals and uranium tend to be found together. The Molybdenum Corp. of America bought the mining claims, and small-scale production began in 1952. Production expanded greatly in the 1960s, to supply demand for europium used as a phosphor in color television picture tubes.
The deposit was mined in a larger scale between 1965 and 1995. During this time, the mine supplied most of the worldwide rare earth metals' consumption. The Molybdenum Corp. of America changed its name to Molycorp in 1974. The corporation was acquired by Union Oil in 1977, which in turn became part of Chevron Corp. in 2005. Along the way, Molycorp absorbed GM's Magnequench along with their patents for neodymium.
In 1998, the mine's separation plant ceased production of refined rare earth compounds. The mine closed in 2002, in response to both environmental restrictions and lower prices for rare earth metals.
Environmental issues? There is a dirty secret that where you find rare earth metals is where you find radioactive ores, and radioactive slurry is a by-product of the separation process of ores. In 1998, chemical processing at the mine was stopped after a series of wastewater leaks. Hundreds of thousands of gallons of water carrying radioactive waste spilled into and around Ivanpah Dry Lake. The mine has been mostly inactive since 2002, though processing of previously mined ore continued.
In 2008, Chevron sold the mine to privately held Molycorp Minerals, LLC - a company formed to revive the Mountain Pass mine. In 2010, most of us in the speaker industry will remember China artificially raised the price of rare-earth elements by restricting exports of neodymium. With this huge opportunity facing them, Molycorp spent hundreds of millions of dollars on a state-of-the-art ore-processing system for rare-earth metals. The program was to turn Mountain Pass into the cleanest, most energy-efficient, most reliable source of rare earth metals on the planet.
Meanwhile, back in China, whether by plan or inadvertently, China's neodymium prices plummeted in 2012 onward, Molycorp couldn't compete and filed for bankruptcy in June 2015. At the time of the bankruptcy, Molycorp had outstanding bonds in the amount of $US 1.4 billion.
For now, we may be in the eye of the storm - calm for the moment, but with the likelihood of trade wars coming and neodymium being a pressure point for electric cars (not to mention loudspeakers!), China may manipulate huge price hikes on neodymium. The Mountain Pass mine could have been pivotal to break this strangle-hold. This resource would seem to be an obvious ace in the hole with both the unlimited reserves and the world's most advanced refining processes, scaled for massive production - just waiting to spring into action during a trade war or other Chinese monopolistic price fixing moves.
Mountain Pass in San Bernardino County, CA, now owned by MP Materials mine, formerly Molycorp Minerals.
Whoops! On July 10, 2017, MP Mine Operations, LLC, a Chinese-led and controlled consortium, purchased the Mountain Pass mine out of bankruptcy. It seems the Chinese bought the Mountain Pass mine including the advanced processing for peanuts ($20 million) and are currently working to recommence operations. I wonder why...
While the present administration at least gives lip service to "America First," when the mining industry representatives met with Trump's chief strategist (at the time), Steve Bannon, to persuade him that the US should nationalize the country's only mine of rare earth minerals, this fell upon deaf ears. Apparently, Mountain Pass was not a higher priority than adding a short stretch of border wall.
Well, we blew that one - but we have one more chance to prepare for China cutting off our supplies of neodymium. Next week, we will discuss another resource, with Neo recycling plants coming online Q1 2019.