|An open pit rare earth mine|
(click to enlarge)
The mining of rare earth elements (also known as REEs) is different from many other strategic materials because of the unique geology of rare earths. Rather than being highly concentrated in ore deposits, most rare earth elements are found in combination with many minerals in very small amounts. This scattered nature of rare earth deposits means that although there are more rare earths than copper or zinc in the Earth's crust, they are far harder to extract in an economically feasible manner. Exploitable deposits of rare earths are often found inside uncommon types of igneous rocks, like alkalines and carbonatites. Rare earth elements are also present in alluvial deposits, and alongside highly valuable iron-oxide copper-gold deposits. As assaying these scattered mineral deposits of REEs is costly, much exploration is still being done for suitable REE mines. Most current production of rare earth elements is within China, where it is mined from carbonates and phosphates. (To read more about this, click here.)
After rare earth-containing minerals are extracted from the ground, they must be refined, separating the rare earth elements from impurities. Because of their low concentration, vast quantities of ore must be extracting, resulting in much of the refining process being performed on site, at the mine. Refining REEs involves chemically treating the ores, with many REEs requiring different chemical techniques for each kind of ore. Typically, REEs are refined by milling the ore, down to fine particles, where it will then be subjected to a series of specific chemical treatments.
The complex nature of refining these ores, along with the massive amount of ore that must be processed, means that there is a large amount of chemical waste and tailings, some of them radioactive, produced by rare earth mines. (For more information on the waste produced, and its damage to environment, read here and here.)
An interesting look into the process of how rare earth elements are produced and the issues currently present in rare earth extraction, are shown in this video of the Bayan Obo Mining District in Baotau, China, which produces nearly half of the supply of all rare earth metals.
|An illegal mountaintop-removal REE mine in China|
(click to enlarge)
Even more damaging than facilities like Bayan Obo are the illegal mines that have sprung up throughout China as small companies bribe officials and quickly pillage an area, extracting REE without any regulation or regard for the environment.
To stop the terrible toll that REE mining is taking on people and the environment in the emerging third world, it is important that we act now to increase the supply of rare earths through recycling, and lessen the demand of rare earths through intelligent consumption (like skipping upgrade cycles and buying refurbished phones). If we could raise the current rate of E-cycling from 25% to 50% we would recycle another 2.37 million tons of electronics annually. I urge everyone to act now by contacting all their friends and family members and offering to help and urging them to recycle all of their E-waste.
Electronics Waste Management In the United States Through 2009. (2011, May 1). Retrieved November 20, 2014, from http://www.epa.gov/waste/conserve/materials/ecycling/docs/summarybaselinereport2011.pdf
Rare Earth Elements. (n.d.). Retrieved November 20, 2014, from http://web.mit.edu/12.000/www/m2016/finalwebsite/elements/ree.html