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Commonly, rare-earth elements with atomic numbers 57 to 61 (lanthanum to promethium) are classified as light and those with atomic numbers 62 and greater are classified as heavy rare-earth elements.
15. Mai 2024 · Heavy rare earth metals are defined by their higher atomic weights relative to light rare earths. They are less common, and some elements within the group are facing shortages as demand...
- Educational Content Specialist
- Summary
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Rare earth elements are a group of seventeen chemical elements that occur together in the periodic table (see image). The group consists of yttrium and the 15 lanthanide elements (lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium). Scandium ...
The rare earth elements are all metals, and the group is often referred to as the \"rare earth metals.\" These metals have many similar properties, and that often causes them to be found together in geologic deposits. They are also referred to as \"rare earth oxides\" because many of them are typically sold as oxide compounds.
Several pounds of rare earth compounds are in batteries that power every electric vehicle and hybrid-electric vehicle. As concerns for energy independence, climate change, and other issues drive the sale of electric and hybrid vehicles, the demand for batteries made with rare earth compounds will climb even faster.
Other substances can be substituted for rare earth elements in their most important uses; however, these substitutes are usually less effective and costly.
From the 1950s until the early 2000s, cerium oxide was a very popular lapidary polish. It was inexpensive and very effective. The recent price increases have almost eliminated the use of cerium oxide in rock tumbling and the lapidary arts. Other types of polish, such as aluminum and titanium oxide, are now used in its place.
Rare earth elements play an essential role in our national defense. The military uses night-vision goggles, precision-guided weapons, communications equipment, GPS equipment, batteries, and other defense electronics. These give the United States military an enormous advantage. Rare earth metals are key ingredients for making the very hard alloys us...
Substitutes can be used for rare earth elements in some defense applications; however, those substitutes are usually not as effective and that diminishes military superiority. Several uses of rare earth elements are summarized in the accompanying table [5].
Rare earth elements are not as \"rare\" as their name implies. Thulium and lutetium are the two least abundant rare earth elements - but they each have an average crustal abundance that is nearly 200 times greater than the crustal abundance of gold [1]. However, these metals are very difficult to mine because it is unusual to find them in concentra...
The most abundant rare earth elements are cerium, yttrium, lanthanum and neodymium [2]. They have average crustal abundances that are similar to commonly used industrial metals such as chromium, nickel, zinc, molybdenum, tin, tungsten, and lead [1]. Again, they are rarely found in extractable concentrations.
The Chinese dominance may have peaked in 2010 when they controlled about 95% of the world's rare earth production, and prices for many rare earth oxides had risen over 500% in just a few years. That was an awakening for rare earth consumers and miners throughout the world. Mining companies in the United States, Australia, Canada, and other countrie...
High prices also caused manufacturers to do three things: 1) seek ways to reduce the amount of rare earth elements needed to produce each of their products; 2) seek alternative materials to use in place of rare earth elements; and, 3) develop alternative products that do not require rare earth elements.
China Buying Resources Outside of China New mineral resource assessments conducted by the United States Geological Survey identified significant resources outside of China. Although China is the world leader in rare earth production, they only control about 36% of the world's reserves. This provides an opportunity for other countries to become impo...
Mines in Australia began producing rare earth oxides in 2011. In 2012 and 2013 they were supplying about 2% to 3% of world production. In 2012 the Mountain Pass Mine came back into production, and the United States produced about 4% of the world's rare earth elements in 2013. Production in Brazil, Malaysia, Russia, Thailand and Vietnam continued or...
Supply and demand normally determine the market price of a commodity. As supplies shrink, prices go up. As prices go higher, those who control the supply are tempted to sell. Mining companies see high prices as an opportunity and attempt to develop new sources of supply.
With rare earth elements, the time between a mining company's decision to acquire a property and the start of production can be several years or longer. There is no fast way to open a new mining property.
If a single country controls almost all of the production and makes a firm decision not to export, then the entire supply of a commodity can be quickly cut off. That is a dangerous situation when new sources of supply take so long to develop.
In 2010 China significantly restricted their rare earth exports. That was done to ensure a supply of rare earths for domestic manufacturing and for environmental reasons. This shift by China triggered panic buying, and some rare earth prices shot up exponentially. In addition, Japan, the United States, and the European Union complained to the World...
The global demand for automobiles, consumer electronics, energy-efficient lighting, and catalysts is expected to rise rapidly over the next decade. Rare earth magnet demand is expected to increase, as is the demand for rechargeable batteries. New developments in medical technology are expected to increase the use of surgical lasers, magnetic resona...
Rare earth elements are heavily used in all of these industries, so the demand for them should remain high.
21. Feb. 2017 · Heavy rare earth elements (HREE) are dominantly mined from the weathering crusts of granites in South China. Although weathering processes occur globally, no economic HREE resources of this type...
- Cheng Xu, Jindřich Kynický, Martin P. Smith, Antonin Kopriva, Martin Brtnický, Martin Brtnický, Toma...
- 2017
1. Dez. 2021 · Heavy rare earth elements (HREEs) containing Gd to Lu plus Y have a series of unique physicochemical properties which endow them critical resources in many fields such as high-tech components, green technologies and material industries. However, the huge demand of HREEs has resulted in sharply reduction of their reserves. Henceforth ...
- Tianchi Liu, Tianchi Liu, Ji Chen, Ji Chen
- 2021
15. Feb. 2023 · Abstract. Rare earth elements (REEs + Y) play an important role in modern industry. Heavy REEs (HREEs) are particularly critical because of their relative scarcity in nature. Global HREE resources are predominantly present in granitoid weathering crusts in southern China.
18. Feb. 2024 · Physicists have found new forms of thulium, ytterbium, and lutetium by breaking apart platinum nuclei with a heavy-ion accelerator. This could help us understand how neutron stars forge the heaviest elements in the Universe.
