In this month’s 90 Second Stem, we will learn what rare earth elements are, what they’re used for and some recent developments regarding how they are extracted. I’m Michael Tung, and I will be your host for today. To start, rare earth elements are 17 elements on the periodic table that are metallic. To clear up a common misconception, I have to point out that rare earth elements, despite what they’re called, are not rare. The reason why they’re called rare is because they’re spread far around the world, that it’s hard to find them all in the same place at the same time. This is in a way good news because we use rare earth elements for many different things such as magnets for computers, electric cars, clean energy, and more. They can also be used in camera lenses, aircraft engines, and so many more products that we use on a day-to-day basis. There have recently been some new discoveries in Japan regarding the way that we extract rare earth elements. Because they’re used by humans on a day-to-day basis, it’s important that we find cleaner ways to mine these minerals and to make sure that they are preserved as well. The island of Minami-tori-shima, may seem like any other Pacific island, but it holds an interesting characteristic. On the surface level of the island is just a weather station and an airstrip, but it also holds many many fish fossils and skeletons. What these fish fossils did was to preserve and hold rare earth elements in, solving a major problem that miners previously had was that the resource was spread thinly around the world. The process that allowed for the perfect storm to arise to trap rare-earth elements is complicated, but essentially what happens is: during the ice age, as the earth cools down, the water patterns from around 34 million years ago are shifted around, resulting a large boom of life near Minami-tori Island. Then after around 100,000 years, the living organisms in the area had run out of nutrients to sustain themselves, resulting in their death. Once they die, their carcass is sunk to the bottom of the ocean, and they become fossilized Calcium and Phosphate. Fossilized phosphate is an excellent rare earth mineral trapper, which by now has trapped over 16 million tons of rare earth elements according to Japanese scientists. That amount is expected to last the world around 420-780 years. The downside to this is that the event to create millions of fish fossils is a one time event. The upside is that many pacific islands may have had the same events happen to them as well, creating an “endless” source of rare earth elements. The next step is for scientists to determine whether or not mining these islands can be environmentally friendly, and what technologies to innovate to make sure that they can be mined safely.
Frazer, Jennifer. “Mining Rare-Earth Elements from Fossilized Fish.” Scientific American, Scientific American, 21 Sept. 2020, www.scientificamerican.com/article/mining-rare-earth-elements-from-fossilized-fish/.
“What Are Rare Earth Elements, and Why Are They Important?” American Geosciences Institute, 1 Feb. 2018, www.americangeosciences.org/critical-issues/faq/what-are-rare-earth-elements-and-why-are-they-important.
“What Are ‘Rare Earths’ Used for?” BBC News, BBC, 13 Mar. 2012, www.bbc.com/news/world-17357863.
