The rare earth metals are, in fact, not that rare.
The most commonly occurring rare earth metals - cerium, lanthanum, neodymium and yttrium - are actually more common in the Earth's crust than lead. And even silver.
While cerium, the most abundant rare earth metal, is more prevalent (60 parts per million (ppm)) than copper, even lutetium (0.5 ppm) and thulium (0.5 ppm), the least abundant, are to be found in the Earth's crust in greater quantities than antimony, bismuth, cadmium and thallium. (The outlier is promethium, which, it appears, is not to be found in the Earth's crust, and which is only used in compound form, of which, to date, some30 have been prepared.)
Abundance of Elements In The Earth's Crust
Note: Abundance (atom fraction) of the chemical elements in Earth's upper continental crust as a function of atomic number.
Many of the elements are classified into (partially overlapping) categories: (1) rock-forming elements (major elements in green field and minor elements in light green field); (2) rare earth elements (lanthanides, La-Lu, and Y; labeled in blue); (3) major industrial metals (global production > ~3x107 kg/year; labeled in bold); (4) precious metals (italic); and (5) the nine rarest "metals" - the six platinum group elements plus Au, Re, and Te (a metalloid).
Source: USGS
So, why are they called the "rare earth" metals? Probably from the uncommon oxide-type minerals, or earths, from which they were originally extracted. The corollary to their abundance is, however, the fact that, to date, their "discovered minable concentrations are less common than for most other ores."
What Are The Rare Earth Metals?
The rare earth metals (aka, REM, rare earth elements [REE] or, sometimes, just rare earths) are a group of 15 chemically similar elements (grouped separately in the periodic table) known as lanthanides. Commercially, the rare earth grouping usually also includes scandium and yttrium, both of which are actually elements above lanthanum in the periodic table.
In more physical terms, these metals range in color from shiny silver to iron gray. As the USGS describes them, they "are typically soft, malleable, ductile and usually reactive, especially at elevated temperatures or when finely divided." At the lower end, cerium has a melting point of 798° C and, at the upper, lutetium has a melting point of 1,663° C.
It will come as no surprise that the unique properties (catalytic, chemical, electrical, metallurgical, nuclear, magnetic and optical) of the REM, and, in particular, both their specificity and versatility, have led to their being used for a wide variety of purposes.
From relative obscurity, they are now important economically, environmentally and technologically.
What Are They Used for?
The range of applications in which they are used is extraordinarily wide, from the everyday (automotive catalysts and petroleum cracking catalysts, flints for lighters, pigments for glass and ceramics and compounds for polishing glass) to the highly specialized (miniature nuclear batteries, lasers repeaters, superconductors and miniature magnets).
The Rare Earths And Some Of Their End Uses
Name | Symbol | Some End Uses |
Cerium | Ce | Catalysts, Ceramics, Glasses, Misch Metal*, Phosphors and Polishing Powders |
Dysprosium‡ | Dy | Ceramics, Phosphors and Nuclear Applications |
Erbium‡ | Er | Ceramics, Glass Dyes, Optical Fibers, Lasers and Nuclear Applications |
Europium‡ | Eu | Phosphors |
Gadolinium‡ | Gd | Ceramics, Glasses, Optical and Magnetic Detection and Medical Image Visualization |
Holmium‡ | Ho | Ceramics, Lasers and Nuclear Applications |
Lanthanum | La | Automotive Catalysts, Ceramics, Glasses, Phosphors and Pigments |
Lutetium‡ | Lu | Single Crystal Scintillators |
Neodymium | Nd | Catalysts, IR Filters, Lasers, Permanent Magnets and Pigments |
Praseodymium | Pr | Ceramics, Glasses and Pigments |
Promethium | Pm | Phosphors and Miniature Nuclear Batteries and Measuring Devices |
Samarium | Sm | Microwave Filters, Nuclear Applications and Permanent Magnets |
Scandium | Sc | Aerospace, Baseball Bats, Nuclear Applications, Lighting and Semiconductors |
Terbium‡ | Tb | Phosphors |
Thulium‡ | Tm | Electron Beam Tubes and Medical Image Visualization |
Ytterbium‡ | Yb | Chemical Industry and Metallurgy |
Yttrium‡ | Y | Capacitors, Phosphors (CRT and Lamp), Radars and Superconductors |
Groups: yttrium and lanthanide (Scandium falls into neither category)
‡ Heavy REM
* Misch Metal is an alloy of rare earth metals used not only for lighter flints, but also, probably more importantly, in purifying steel by removing oxygen and sulfur.
Separately, or as compounds, various rare earth metals are used also in the production of superalloys.
REM are now especially important, and used extensively, in the defense industry. Some of their specific defense applications include: anti-missile defense, aircraft parts, communications systems, electronic countermeasures, jet engines, rockets, underwater mine detection, missile guidance systems and space-based satellite power.
USGS figures for 2006 indicate that the three main uses of REM in the U.S. were: automotive catalytic converters (25%), petroleum refining catalysts (22%) and metallurgical additives and alloys (20%).
Source: USGS
In many of these applications, the REM are used in the form of low-cost compounds. As oxides, they are used extensively in the ceramics and glass industries and, in addition, for various metallurgical uses. Indeed, it has been estimated that only 25% of mined REM-bearing materials are actually processed to extract individual metals.
The REM most commonly used as separated metals are: cerium, europium, gadolinium, neodymium, samarium and terbium.
Rare Earth Metals Supply
From having been a major producer (and consumer) of REM (from the Mountain Pass mine in the Mojave Desert, Calif.) until the mid-80s, the U.S. now no longer mines any REM. The world's major producer is China (particularly from its Bayan Obo mining operation in Inner Mongolia), with considerably lesser amounts coming from Brazil, India and Russia. Since 2000, domestic REM consumption in China (which now accounts for over half of the country's overall REM products) has exceeded that of the U.S.
Global Rare Earth Metal Oxide Production - 1950-2006 (‘000s Tonnes)
Source: Russian Journal of Non-Ferrous Metals (from USGS)
While REM deposits in China and the U.S. are primarily to be found in the mineral bastnäsite (80-90% of all raw materials produced), elsewhere - and in particular in Australia, Brazil, India, Malaysia, South Africa, Sri Lanka and Thailand - they are usually to be found in the mineral monazite. (There are also monazite resources both in China and the U.S.) Mining monazite can, however, be a little tricky, as the ore tends to contain the radioactive elements thorium (see Cobalt: More Than Just Blue) and radium.
In addition, there are also REM-containing ion-absorption ores in the south of China. Importantly, these last contain around 80% of the world's known resources of the less-widespread heavy, yttrium group, metals.
World Mine Production (Tonnes)
Country | 2006 | 2007 |
China | 119,000 | 120,000 |
India | 2,700 | 2,700 |
Brazil | 730 | 730 |
Malaysia | 200 | 200 |
Thailand | - | - |
Australia | - | - |
U.S. | - | - |
Other Countries | NA | NA |
Total (rounded) | 123,000 | 124,000 |
Source: USGS
Although it mines no REM of its own, in 2007, the U.S. remained a major importer, exporter and consumer. From 2003-2006, China accounted for some 94% of its REM-related imports.
While not yet actually recommencing mining operations (for environmental, regulatory and market reasons), toward the end of 2007, Molycorp Inc. (wholly-owned by Chevron) resumed operating its rare earth separation plant at Mountain Pass. The company continues to sell bastnäsite concentrates and REM intermediaries, together with refined products, from its existing mine stocks. Permits to recommence mining are still pending.
Rare Earth Metals Demand
Domestic demand in the U.S., as well as the demand for REM globally, remained strong in 2007, and have continued so in 2008. This has been true both for mixed rare earth compounds and the metals and their alloys. According to the USGS: "The trend is for a continued increase in the use of rare earths in many applications, especially automotive catalytic converters, permanent magnets, and rechargeable batteries."
Forecast Growth Of Rare Earth Metals Usage
Element | Application | Consumption (Tonnes p.a. of REO) | Growth Rate (% p.a) | |
2006 | 2012 | |||
Ce, La, Nd, Pr | Battery Alloy | 17,000 | 43,000 | 17 |
Dy, Nd, Pr, Sm, Tb | Magnets | 20,500 | 42,000 | 13 |
Eu, Tb, Y | Phosphors | 8,500 | 14,000 | 9 |
Ceramics | 5,500 | 9,000 | 9 | |
Others | 8,000 | 13,000 | 8 | |
Ce, Nd, La | Catalysts | 21,500 | 32,000 | 7 |
Ce, La, Pr | Polishing Powder | 14,000 | 21,000 | 7 |
Ce, Er, Gd, La, Nd, Yb | Glass Additives | 13,000 | 14,000 | 1 |
Total | 108,000 | 188,000 | 10 | |
REO = rare earth oxide
Source: Roskill HK Rare Earth Conference, November 2007
The prices of most REM rose in 2007, and with the exception of neodymium and praseodymium (both metal and oxides) and terbium (oxide), the prices of most REM (metals and oxides) have either remained the same, or continued to rise in 2008.
Price - US$/Kg | ||||
Name | Oxide | Metal | ||
End-2007 | End-Oct 2008 | End-2007 | End-Oct 2008 | |
Cerium | 3.60 | 3.80 | 7.10 | 10.50 |
Dysprosium | 94.00 | 118.00 | 125.00 | 153.00 |
Erbium | 35.00 | 35.00 | N/A | N/A |
Europium | 368.00 | 525.00 | 560.00 | 700.00 |
Gadolinium | N/A | N/A | 25.00 | 28.00 |
Lanthanum | 4.60 | 8.00 | 6.00 | 13.00 |
Lutetium | 550.00 | 550.00 | N/A | N/A |
Neodymium | 30.00 | 20.00 | 40.00 | 29.00 |
Praseodymium | 28.00 | 20.00 | 37.00 | 29.00 |
Samarium | 4.40 | 4.40 | 14.00 | 26.00 |
Terbium | 633.00 | 621.00 | 750.00 | 793.00 |
Ytterbium | 55.00 | 55.00 | N/A | N/A |
Yttrium | 12.00 | 12.00 | 29.00 | 42.00 |
Misch Metal (48% Ce) | 6.00 | 8.00 | ||
Misch Metal (25% La) | 12.00 | 14.00 | ||
Source: Tianjiao International
With such strong domestic demand for REM in China, there are now controls on production and exports (tariffs and quotas). And in some places, because of environmental concerns, among other things, there are both mining restrictions and mining quotas.
According to Roskill's 2007 report on the economics of rare earths and yttrium, this has "brought fundamental change to the global industry, taking it from oversupply to demand shortages."
Indeed, in its report, Roskill envisaged that, with demand growth for rare earths forecast at 8-11% per annum, and should China's strict control persist, there will be a significant need for "new non-Chinese capacity in the next 3 to 4 years."
2007 - Supply/Demand Forecast
Source: Roskill
Opportunities In Rare Earths
As with the minor metals, there are no exchanges on which REM are traded. Both the physical metals and their different oxides can, however, be bought from various specialist rare earth companies.
It seems reasonable to assume that there will always be demand for rare earths metals. While there are substitutes, these are usually not as effective. Since no REM are currently mined in the U.S., and Molycorp is a wholly-owned subsidiary of Chevron, no direct investment in any significant U.S. mining operations for these metals is possible. Looking overseas, there are, however, some opportunities for exposure.
India, unfortunately, is out, as all three rare earth production companies are government-owned.
A recent news snippet about the Japanese chemical group Showa Denko(Bloomberg Ticker - SHWDF:US) was of particular interest on two counts. Not only did it state that the company had set up a joint venture to extract dysprosium in Vietnam, but also that it was doing so because it wanted to secure a "stable supply" of rare earth magnetic materials as, currently, it relies on China - where, indeed, it currently has two subsidiaries (Baotou and Ganzhou).
China
If, however, the world's largest REM producer is of interest, then, among the Chinese companies mining REM in Bayan Obo, is the quoted Inner Mongolia Baotou Steel Rare-Earth Hi-Tech Co Ltd (Baogang) (Bloomberg Ticker - 600111:CH).
Quoted companies mining REM elsewhere in China include: China Rare Earth Holdings Ltd (Bloomberg Ticker - CREQF:US), Aluminum Corporation of China (aka Chinalco) (Bloomberg Ticker - ACH:US), Neo Material Technologies (Bloomberg Ticker - NEM:CN).
Recently, however, the mines in Sichuan were shut down, and there are strict quotas in places in Fujian, Guangdong, Hunan and Jiangxi, where there has been severe environmental damage.
Australia
In Australia, there are currently a number of rare earth mining projects at various stages of development.
According to an ASX announcement at the beginning of July this year, the "Demonstration Pilot Plant" at Alkane Resources' (Bloomberg Ticker - ALK:AU) Dubbo Zirconia project was set to go 24/7 in late July, and it stated that "(l)aboratory scale testing for recovery of the rare earth elements is scheduled to commence in July."
Arafura Resources (Bloomberg Ticker - AFAFF:US) expects the rare earths processing plant at its Nolans Project in the country's Northern Territory to be in production in 2011.
Based on November 2005 figures, the company compared its Nolans resource with some others around the world.
Source: Arafura Resources Limited
At its Mount Weld project in Western Australia, Lynas Corporation(Bloomberg Ticker - LYSCF:US) completed its first mining "campaign" in May. Based on figures updated in March this year, the company believes its resources at the project now amount to some 12.24 million tonnes at 9.7% rare earth oxide, which will produce some 1,124,000 tonnes of REO.
Canada
In addition to Neo Material Technologies out of Toronto, with its operation in China, there are three other Canadian companies involved, to a greater or lesser extent, in REM in Canada itself.
Avalon Ventures Ltd (Bloomberg Ticker - AVL:CN) has its Thor Lake Project near Yellowknife in Canada's Northwest Territories with, according to the company, "[e]xceptional enrichment in Neodymium & Heavy REE."
VMS Ventures (Bloomberg Ticker - VMS:CN), out of Vancouver, has its Eden Lake Carbonatite Complex in Manitoba, where REM were discovered in 2003.
Great Western Minerals Group (Bloomberg Ticker - GWG:CN), out of Saskatoon in Saskatchewan, has its Hoidas Lake Rare Earth Project which, in the words of the company, "...is North America's most advanced Rare Earth Element (REE) property in development..." and "...has the potential to supply at least 10% of North America's consumption of REE for many years."
Finally, Canada's Rare Element Resources (Bloomberg Ticker - RES:CN), has not only gold on its Bear Lodge, Wyo., property, but also, in its words, "significant high-grade rare-earth elements."
For those interested in looking "downstream," there are a number of REM producers internationally, especially in Japan. In the U.S., however, apart from Chevron's Molycorp, both France's chemical company Rhodia(Bloomberg Ticker - RHA:FP), and WR Grace's (Bloomberg Ticker - GRA:US) Grace Davison division are actively involved in processing rare earths.
Afterwords
First, it has been estimated that current global consumption of REM now accounts for around 70-75% of their total production. This leads one to believe that considerable quantities of mined REO remain, as yet to be processed.
Second, the mineral ore resources currently mined to produce REM contain different groups of metals, not just particular, individual, metals in isolation. So, instead of some of these metals being by-products of other metals, as, say, rhenium is of moly, and moly is of copper, they are essentially "co-products" - mine for one and the others come free.
The corollary to this, however, is that the economics of mining on such a "volume" basis could lead to it just not being viable to mine such ore resources for one or two REM alone, especially if the other metals contained in the REO do not "pay their way." In future, therefore, the composition of a mine's REO resources - as opposed just to the volume of ore it can produce - may well become critical to that mine's economic viability.
Third, even though rare earth metals are classified as critical minerals in the U.S. National Academies' "criticality matrix," the U.S. National Defense Stockpile at present contains none.
Resources
