Rare earth elements or rare earth metals are one of 17 chemical elements within the periodic table. Of those rare earth elements, 15 are in the lanthanide series and include yttrium and scandium.
Johan Gadolin is considered the “Father of the Rare Earths.” In 1792, the Finnish chemist identified minerals similar to each other. Yet, they were different from the common earth elements. So, he named the group “rare-Earth elements.”
Despite the name, rare earth elements (REE) are generally abundant on our planet. But, unlike other elements found in areas or large deposits, REEs scatter in tiny quantities throughout the earth’s crust. Thus, extractions of REEs come from ores and minerals such as:
- fluorite, and,
Mining them is expensive, difficult, and hazardous to mine. While the challenges inherent in their mining and extraction affect supply, the demand is high due to their unique properties. These include:
- the ability to form lightweight, yet strong magnetic alloys;
- optical properties like the ability to illuminate and produce coherent light; and,
- the ability to increase chemical reactions.
Elements in the rare earth group are essential for hundreds of applications and industries such as:
- military defense systems,
- renewable energies,
- nuclear energy,
- hybrid vehicles,
- petroleum refining,
- electronic devices,
- fiber optics,
- polished glass products,
- lighting, and,
Where on Earth?
Currently, China supplies the majority of REEs. Mine productions exist in Brazil, India, Malaysia, Russia, and the United States. Cerium and lanthanum, the most plentiful of the rare earth group, make up about 50 and 25 percent of world production, respectively. Thus, to meet demand, mining activities are expanding in countries like Canada, Australia, and the US. Additionally, in Greenland and other Arctic areas REEs (as well as oil, gas, and minerals) are now accessible due to the recent retreat of sea ice caused by climate change. Various countries vie for control of these resources. Manganese modules are another potential source of REEs. The modules are deposited on sea beds. Thus, they are difficult to retrieve. Currently, Japan is developing new techniques to harvest deep-sea nodules.
Recycling of REEs holds promise to satisfy demand. As a result, the US Geologic Survey and the Department of Interior continue research on how to reclaim and recycle these crucial elements.
Note: This article was originally published in an Earth Systems newsletter in 2013 and written by Margaret Lange. It has been re-edited for the web.