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, some 30 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
The National
Academies
Roskill
Russian Journal of Non-Ferrous Metals
Tienjiao
International
U.S. Geological Survey (USGS)