Lithium Resources Ihor Kunasz
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Lithium Resources
Ihor Kunasz
INTRODUCTION that resists thermal cracking. Perhaps the most recognized applica-
The second half of the 20th century saw a dramatic shift in lithium tion is CorningWare, in which lithium imparts a negative coeffi-
carbonate (and some lithium chloride) production from the usual cient of expansion when heated, which allows the ceramic to be
pegmatite sources to brines. Today, all lithium carbonate, which is used from refrigerator to oven without shattering.
the basis of various downstream lithium chemicals, comes from the In 1953, the Atomic Energy Commission (AEC) required
brines of the Salar de Atacama, Chile, and Clayton Valley, Nevada large amounts of lithium hydroxide from which the lithium-6 iso-
(United States). Lithium chloride is also produced from the Salar del tope was separated and reserved for use in producing the hydrogen
Hombre Muerto, Argentina. Various other salars and playas such as bomb. For about 5 years, the government was the largest consumer
those of China, Bolivia, Argentina, and Tibet are being evaluated for of lithium. After the AEC contracts expired in 1960, the lithium
future lithium chemical production. The industry was once domi- industry, faced with vast overcapacity, sought desperately to
nated by two major U.S. producers, until a third producer from Chile develop some commercial markets. Though not an overnight suc-
started production of various salts, including lithium carbonate. This cess, it soon became a firmly established supplier to basic indus-
shift in sources led to the shutdown of both U.S. pegmatite opera- tries such as ceramics, lubrication, aluminum reduction, and
tions. Australia, Canada, and Zimbabwe have continued to supply pharmaceuticals. If certain technical issues are resolved, thermonu-
lithium mineral concentrates for the ceramic and glass industry and clear fusion, which requires lithium as the primary fuel, could solve
other applications. Minor producers in Brazil, Portugal, Russia, and much of the world’s energy requirements.
the People’s Republic of China mine various lithium minerals. One Today, even though lithium products are widely used in
new U.S. supplier of lithium chemicals came on stream using the households, factories, and laboratories, lithium’s presence often
depleted lithium hydroxide government stockpile. goes unrecognized. Lithium may be as close to the average person
When it was first recognized, lithium was an oddity that as a medicine chest, a television, a swimming pool, or a calculator.
became an important commodity owing to its unusual properties. Lithium is found in minerals, clays, and brines in various parts of
In 1854 in Germany, R. Bunsen and A. Mathiessen used an elec- the world. High-grade lithium ores and brines are the present
trolytic process to prepare lithium as a free metal from molten lith- sources for all commercial lithium operations. Economical brine
ium chloride. They prepared lithium carbonate, lithium chloride, sources of lithium were rare until several salars in South America
and then lithium metal from zinnwaldite, a lithium-bearing mica. were discovered to contain significant deposits of lithium.
Lithium-bearing minerals were sometimes used as exotic additives Lithium was first produced from zinnwaldite in Germany.
to ceramic compositions. This was followed by the production of spodumene from the
Not until World War II were the special properties of lithium Black Hills of South Dakota, where log-sized spodumene crystals
compounds fully investigated and exploited. A compact, light- were mined. The WWII exploration for strategic elements (tin,
weight source of hydrogen was needed for use in emergency- tantalum, and others) resulted in the discovery of the pegmatite
signaling balloons. Lithium hydride was found to be ideal for this fields in North Carolina (Kesler 1961), where two major lithium
purpose. Lithium was also used in alkaline batteries in submarines. mineral and chemical production centers developed. During the
Later, greases containing lithium stearate were found to lubricate at 1950s lepidolite from Southern Rhodesia (Zimbabwe) was
both very high and very low temperatures. For the first time, the imported for conversion to lithium hydroxide at a Texas plant for
same grease could be used for multiple purposes over a wide range producing the hydrogen bomb. After the depletion of the lepidol-
of operating conditions. ite, a spodumene zone was outlined, resulting in the production of
With rocketry came the search for materials that could with- high-grade spodumene concentrates. Numerous lithium pegma-
stand the extreme temperatures of high-speed travel through the tites were also discovered in Canada. Spodumene concentrates are
atmosphere. A ceramic composition containing lithium was devel- produced at the Tanco mine in Manitoba. In the 1980s spodumene
oped that expanded very little and resisted cracking during rapid was identified during tantalum mining and exploration in Western
extreme temperature change. This lithium-containing material Australia, resulting in the production of spodumene concentrates
pyroceram was the forerunner of modern glass-ceramic cookware at Greenbushes.
599600 Industrial Minerals and Rocks
Lithium chemical production was shifted when the Silver chemical make-up unaccounted for. Further work resulted in the
Peak brine deposit, originally evaluated as a potash source, resulted extraction of a compound with chemical properties, suggesting that
in the unique production of lithium carbonate in 1966. Although an unknown element was present. Since the new element had been
lithium had been identified in 1936 in the brines of Searles Lake, found in chunks of petalite, Arfwedson called it “lithium,” from the
California, the lithium diphosphate scale generated during the Greek word lithos, meaning stone.
boron recovery process was considered more of a hindrance than an The geochemistry of lithium has been extensively studied, and
economic product. Put into production in 1966, the Silver Peak Goldschmidt (1937), Rankama and Sahama (1950), Hortsman
brine was, for almost 20 years, the only brine source of lithium car- (1957), and Cerny (1991) summarized the work.
bonate production in the world. In 1969, the Chilean Instituto de The distribution of lithium in igneous rocks is controlled by
Investigaciones Geologicas (IIG) identified unusually high concen- its size and its charge, and by the (MgO+FeO)/Li2O ratio. In the
trations of potassium and lithium at the periphery of the Salar de early stages of crystallization of a magma, that ratio is very large.
Atacama in Northern Chile (Moraga et al. 1974). After confirming Consequently, both magnesium and iron are removed by ferromag-
the high concentrations, Foote Mineral initiated a feasibility study nesian minerals in preference to lithium, which is then concentrated
in 1975, and the Sociedad Chilena de Litio (SCL) began producing in the residual magma. The result is an enrichment of lithium in
lithium carbonate from the southern sector of the salar in 1986. silicic rocks and pegmatites (Strock 1936).
Several companies attempted to develop the northern portion of the Pegmatites are coarse-grained igneous rocks formed by the
salar. Eventually, Sociedad Quimica y Minera (Soquimich or SQM) crystallization of postmagmatic fluids. Minerals within pegmatites
developed the deposit and produced a number of chemicals, includ- can also form by metasomatism (Jahns 1955). Genetically the peg-
ing potassium chloride, potassium sulfate, lithium carbonate, and matites are associated with neighboring intrusives. Mineralogically,
boric acid. From a nonproducer before 1988, Chile has become the granitic pegmatites contain feldspar, quartz, and mica as the main
world’s major supplier of lithium carbonate (Ober 2002). constituents and a variety of exotic elements such as lithium, beryl-
The Lithium Division of FMC Corporation explored the Salar lium, tantalum, tin, and cesium, which may or may not occur in
del Hombre Muerto in the Altiplano of Argentina and produces lith- economically significant concentrations.
ium chloride from the brine via a patented ionic exchange process. Detailed studies by numerous investigators (Cameron et al.
As a result of extensive exploration for brine deposits, 1949, 1954; Hanley, Heinrich, and Page 1950; Jahns 1952, 1955;
prompted by lithium production development in Chile, several Page et al. 1953; Norton and Schlegel 1955; Cerny 1991) indicate
chemical-rich deposits were identified and explored in Argentina, that many pegmatites exhibit an internal zonal arrangement, with
Bolivia, the People’s Republic of China, and Tibet. The shift in lith- each zone containing a specific suite of minerals. The lithium min-
ium carbonate production from pegmatites to brines closed the two erals are usually found in the intermediate zones, and, although as
unzoned pegmatite operations of Chemetall Foote Mineral Com- many as 13 zones have been recognized (Cameron et al. 1949), a
pany and the Lithium Division of FMC in North Carolina. Zoned complete zonal arrangement is rarely found. Zoning of pegmatite
pegmatites, which contain high-grade spodumene, continue to be bodies has also been observed regionally. The regionally zoned
important sources of lithium mineral concentrates for the various pegmatite sequences exhibit mineral assemblages and complexity
ceramic and glass industries. according to their respective distance from the granitic bodies to
which they are genetically related. Various theories have been pro-
GEOCHEMISTRY OF LITHIUM posed for the genesis of pegmatites. Cerny (1991) offered convinc-
Lithium is a silvery-white metal that is slightly harder than sodium ing evidence that rare metal pegmatites are essentially magmatic
but softer than lead. It is the lightest of all the metals, with a density phenomena. Although pegmatites exhibit a broad diversity of
of 0.534 g/cm3, or about half that of water. It has an atomic weight paragenetic, geochemical, and structural styles, pegmatites have
of 6.938, an ionic radius of 0.68 Å, and a charge of +1. Lithium is crystallized from a volatile-rich melt enriched to various degrees in
the third element in the periodic table and the first element in Group lithophile elements. From a practical exploration standpoint,
I, the alkali metals group. Like the other metals in the group— Cerny concluded that Late Archean and Early Proterozoic fields
sodium, potassium, rubidium, and cesium—it is so chemically are possibly the most productive, and that lower amphibole facies
active that it never occurs as a pure element in nature; it is always of volcano-sedimentary rocks are the main hosts for pegmatites.
bound in stable minerals or salts. Lithium is also found in small proportions in a variety of
Some lithium compounds show a great resemblance to Group rocks. The average lithium content of igneous rocks is estimated at
II, the alkaline earth metals. For example, the water solubility of about 28 ppm Li. Sedimentary rocks contain an average of 53 ppm
lithium hydroxide is substantially lower than that of other alkali Li, and the highest concentrations are recorded in shale (Hortsman
hydroxides. In general, lithium’s physical and chemical properties 1957). Volcanic rocks, particularly obsidian, contain high concen-
stem from its atomic structure. An atom of lithium consists of a trations of lithium (Shawe, Mountjoy and Duke, 1964; Price et al.
nucleus (three protons and either three or four neutrons) with three 2000). Unusual amounts of lithium are found in the clay mineral
electrons orbiting in two shells. The inner shell (the helium shell) hectorite, which is expandable and belongs to the magnesian end
contains two electrons and is chemically inert. The outer shell con- member of the smectite (montmorillonite) group.
tains only one electron. Lithium, more than any other alkali metal, Lithium is also present in significant amounts in waters associ-
tends to eject this electron from its outermost shell. The resulting ated with geothermal areas (White 1957) in Iceland (Rejkavik), New
lithium ion carries a positive charge (+1). In solid metal, individual Zealand (Waikarei), California (Imperial Valley), and Mexico (Agua
lithium atoms are arranged geometrically in a cubic lattice and can Prieta geothermal field). Very high concentrations (up to 47 ppm Li)
transfer a negative charge from place to place. This electron move- have been recorded in the El Tatio geothermal field, located north of
ment makes lithium metal an excellent electrical conductor. the Salar de Atacama (Ide and Kunasz 1989). It is also associated
A Swedish scientist, Johan August Arfwedson, discovered with certain oil well brines (Mayhew and Heylmun 1966). Lithium
lithium in 1817 in the laboratories of Berzelius. He analyzed the occurred in higher concentrations in certain desert basin brines of
content of a mineral called petalite from Utoe Island, Sweden. The California (Searles Lake), Nevada (Clayton Valley), and Utah (Great
results of the analysis left a sizable percentage of the sample’s Salt Lake), and in a number of salars in Chile (Atacama, Pedernales,Lithium Resources 601
and others), of which the Salar de Atacama is the richest; Bolivia Petalite
(Salar de Uyuni); Argentina (Salar del Hombre Muerto, El Rincon, Petalite, LiAlSi4O10, is a monoclinic mineral with a framework sil-
and others); Tibet (Lake Zabuye), where natural lithium carbonate icate structure. Its color is grayish white and more rarely pinkish. It
was discovered (Holland et al. 1991); and the People’s Republic of has two cleavage directions, which form an angle of 38.5°. The
China (Qinghai Basin). basal cleavage is perfect.
LITHIUM MINERALS The theoretical lithium content of petalite is 2.27%. In com-
mercial deposits it ranges from 1.6% to 2.1% Li. Sizable deposits
Although lithium occurs in some 145 minerals, only spodumene, of petalite occur with lepidolite in Zimbabwe (Bikita), Namibia
lepidolite, petalite, and some other minerals such as amblygonite (Karibib), Brazil (Aracuai), Australia (Londonderry), the former
and eucryptite have been commercial sources of lithium. Today, the U.S.S.R. (eastern Transbaikalia), Sweden (Utoe), and Canada (Ber-
principal sources of lithium ores and chemicals are spodumene and nic Lake).
petalite. In certain pegmatites there is evidence that petalite alters to a
Spodumene mixture of spodumene and quartz. For the Bernic Lake pegmatites
of Manitoba, Cerny and Turnock (1971) described pseudomorphs
Spodumene, a lithium aluminum silicate (LiAlSi2O6), is a mono- of spodumene and quartz after petalite, commonly referred to as
clinic member of the pyroxene group. It has a very pronounced SQI, according to the following reaction: petalite (spodumene +
cleavage plane (110), which results in typically lath-shaped parti- 2quartz).
cles on breaking. The color of spodumene is variable, being nearly
white in the low-iron variety and dark green in iron-rich crystals. Eucryptite
When clear, spodumene is considered a gemstone. Three varieties Eucryptite is also a lithium aluminum silicate that is deficient in sil-
are known: hiddenite, the green variety from Alexander County, ica. It has a formula LiAlSiO4 and can contain 5.53% Li. The only
North Carolina, first discovered in Brazil; triphane, the yellow vari- large deposit of eucryptite is found in Zimbabwe (Bikita), where its
ety also from Alexander County; and the lilac-colored kunzite from occurrence with quartz suggests spodumene origin (Westenberger
the Pala District in California, and in Brazil and Afghanistan. 1963). The grade of the eucryptite is 2.34% Li. Eucryptite has also
Spodumene undergoes pseudomorphic alteration to a variety of been reported in Connecticut (Branchville mica mine); New Mex-
minerals. Norton and Schlegel (1955) described spodumene replace- ico (Harding mine); Manitoba (Tanco mine); Ontario (Nakima
ment by quartz, albite, perthite, muscovite, beryl, amblygonite, apa- mine); and North Carolina (Foote mine).
tite, and tourmaline. Weathering commonly alters spodumene to
kaolinite and to montmorillonite. Amblygonite
Spodumene constitutes the most abundant commercial source Amblygonite, with the generalized formula LiAl(PO4)(F,OH), is the
of lithium minerals. Theoretically it may contain up to 3.7% Li, but fluorine-rich end member of a phosphate series and montebrasite rep-
the actual lithium concentration ranges from 1.35% to 3.56%, prob- resents the hydroxyl-rich end member. It occurs in white to gray
ably as a result of sodium and potassium substitution for lithium. masses. Most cleavage planes are pearly; others are vitreous.
Spodumene concentrates typically contain 1.9% to 3.3% Li. Spo- Amblygonite weathers to earthy apatite, wavellite, and other lithium-
dumene occurs in many pegmatite belts around the world and was deficient phosphates. Although amblygonite may contain as much as
the conventional source of lithium concentrates and chemicals in 4.74% Li, most commercial ores carry 3.5% to 4.2%. Amblygonite
the United States (North Carolina) until the discovery of brines has been mined in Canada, Brazil, Surinam, Zimbabwe, Rwanda,
closed the only two spodumene mines in North Carolina. Spo- Mozambique, Namibia, and the Republic of South Africa.
dumene occurs in many countries: Sweden (Utoe), Austria
(Koralpe), Brazil (Minas Gerais), Argentina, Canada (Manitoba, Hectorite
Quebec, and Northwest Territories), Zimbabwe (Bikita), Demo- Lithium also occurs in significant concentrations in the mineral
cratic Republic of the Congo (Manono and Kittolo), Australia hectorite, a trioctahedral smectite. The purest deposit is found at
(Greenbushes), the Russian Federation (Chita region), and the Peo- Hector, California, where the white clay is exploited for its swelling
ple’s Republic of China (Altai Mountains). characteristics in cosmetic applications. The lithium concentration
in the hectorite is 0.53% Li. Hectorite has also been identified in
Lepidolite Clayton Valley (Kunasz 1970) and McDermitt, Nevada (Glanzman,
Lepidolite is a phyllosilicate with the general formula K2(Li,Al)5–6 McCarthy, and Rytuba 1978).
{Si6–7Al2–1O20}(OH,F)4. The chemical variability expressed in the
formula stems from a structural complexity attributed to a mixture CONTINENTAL BRINES
of polymorphs, which include muscovite, lithium muscovite, and Lithium is found in commercial quantities in certain continental
polylithionite (Winchell 1942). On the other hand, Foster (1960) and brine deposits. The brines, volcanic in origin, are present in desert
Deer, Howie, and Zussman (1962) suggested that there is a continu- areas and occur in playas and saline lakes where dilute lithium solu-
ous series between muscovite with a 2M1 structure to lepidolite with tions have been concentrated by solar evaporation. In Searles Lake,
1M, 2M2, and 3T structures. The structural transition takes place where production of dilithium phosphate began in 1938, the lithium
when the lithium oxide content in the mica reaches 1.53%. concentration is 70 ppm Li. In Clayton Valley, Nevada, the lithium
The lithium concentration in lepidolite ranges from 1.53% to a concentration in brines varies from 100 to 300 ppm. Lesser concen-
possible theoretical maximum of 3.6%. In commercial deposits the trations of lithium (28 to 60 ppm Li) are found in the Great Salt
concentrations are more normally 1.4% to 1.9% Li. In addition to Lake of Utah.
lithium, lepidolites also carry substantial concentrations of rubid- Following the discovery of lithium in the brines of the Clayton
ium and cesium (Deer, Howie, and Zussman 1962). Valley, Nevada, exploration revealed the presence of lithium in other
The major commercial deposits of lepidolite are in Zimbabwe playas and salars in the world (Kunasz 1994). High concentrations
(Bikita), Namibia (Karibib), Canada (Bernic Lake, Manitoba), Bra- of lithium have been recorded in several salars in Argentina (Salar
zil (Minas Gerais), Portugal, and Spain. del Hombre Muerto, 200 to 2,000 ppm Li); Bolivia (Salar de Uyuni,602 Industrial Minerals and Rocks
100 km
The salars or playas fall within three general types, as illus-
trated in Figure 1. Clayton Valley is the smallest of the three. Its
total surface area covers approximately 100 km2. The Salar de Ata-
15–20 m Halite
Clay
cama basin has an approximate surface area of 3,000 km2, whereas
the salt nucleus proper covers an area of approximately 1,400 km2.
Uyuni, Bolivia
The Salar de Uyuni, on the other hand, occupies a very large sur-
40 km face area of approximately 10,000 km2, and thus represents the
largest such desert basin in the world. The idealized stratigraphic
column of each of the three basins indicates significant differences
between them as well and reveals their individual historical evolu-
Halite tion. Clayton Valley underwent alternating dry–wet climatic cycles
300–400 m
Volcanics
under conditions of structural instability. The Salar de Atacama
? formed under an intense evaporative cycle with associated major
?
subsidence. The Salar de Uyuni appears to have undergone a single
evaporitic cycle with little associated subsidence. When the basins
Atacama, Chile
surfaces are predominantly composed of silts and clays with some
3 km salt incrustation, they are referred to as playas. If the surface is pre-
dominantly salt (with or without polygonal cracks), they are called
Clay Halite
salars (English) or salares (Spanish).
100–300 m
Clayton Valley, Nevada
The Silver Peak playa in Clayton Valley is known to be a complex
Silver Peak, Nevada
system (Zampirro 2004), possibly because it has been extensively
Figure 1. Idealized cross sections of three basins
studied, having produced lithium for some 35 years. It can be con-
sidered an intermediate between the Salar de Uyuni and the Salar
de Atacama because it incorporates the structural elements of the
Salar de Atacama but underwent fluctuating arid and wet climatic
100 to 700 ppm Li); Chile (Salar de Atacama, 1,000 to 7,000 ppm
cycles. The basin consists of interbedded fine-grained sediments
Li); Tibet (Lake Zabuye, 700 to 1,000 ppm Li); and the People’s
and halite, some volcanic ash layers, and some tufas. This is consis-
Republic of China (Qinghai, 100 ppm Li; Yiliping, 300 ppm;
tent with the paleohydrologic regimes in the southwestern Great
Tajiner, 350 to 400 ppm Li).
Basin, although obvious breaks such as those reported by G.I.
Brines are the predominant sources of lithium carbonate in the
Smith (1966) at Searles Lake have not yet been recognized.
world today. Much has been done on the chemistry of these brines,
Although the halite layers in the section contain large lithium
revealing that although playas and salars are similar in many
reserves, production comes mainly from an unconsolidated volca-
respects, they nevertheless exhibit individual characteristics
nic ash aquifer and additional reservoirs identified by subsequent
(Kunasz 1980). Lithium-bearing salars or desert basins have the
exploration. Structure maps of the main volcanic ash indicate that
following similar characteristics: they occur within Tertiary or
some portions of the basin subsided as much as 150 m during sedi-
Recent volcanic belts, they are closed structural depressions, and
mentation. Several sources have been identified for the lithium con-
they occur within the desert areas of the earth. These may then be
tained in the Quaternary playa sediments (Figure 2) and in the
considered the fundamental requirements for the occurrence of eco-
lithium-bearing aquifers (Figure 3):
nomic lithium brines.
The first requirement simply establishes the source of lith- • Geothermal fluids issuing from faults on the eastern side of
ium. The volcanic environment supplies the lithium either directly the playa; sampling along a fault zone show a substantial lith-
through hot springs or geothermal solutions or indirectly through ium enrichment (Kunasz 1970)
the leaching of lithium-bearing volcanic or clastic sediments or by • Increased lithium concentrations in the Tertiary lacustrine sed-
the recycling of trapped lithium-bearing solutions. This condition iments exposed on the eastern side of the basin compared to
is met by all three major salars: Clayton Valley, Salar de Atacama, the northern sediments (Kunasz 1970)
and Salar de Uyuni all occur in areas with abundant volcanic • Rhyolitic rocks with high lithium contents on the east side of
rocks. The second requirement provides the necessary mechanism the basin (Price et al. 2000)
for retaining the dilute solutions introduced into the basin. Strong
structural control is evident in Clayton Valley, Nevada, and in the • Concentration of lithium in the Quaternary basin by natural
Atacama Area, Chile. Direct structural control is not obvious for solar evaporation
the Salar de Uyuni. Finally, all potentially commercial lithium These conditions resulted in the accumulation of lithium-rich
concentrations are the result of concentration by solar evaporation. sediments and enriched brine in the southeastern portion of the
With the exception of the Imperial Valley geothermal field and oil- present playa. This sector is the principal source of the brine fed to
field brines where lithium concentrations as high as 280 ppm have the 4,000 acres of solar evaporation ponds in which the lithium
been recorded, high lithium concentrations are not primary but chloride is concentrated (Zampirro 2004).
secondary phenomena, caused by concentration under proper cli-
matological factors. Although the fundamental character of the Salar de Atacama, Chile
salars is similar, cursory examination of the three lithium-rich The Salar de Atacama is in northern Chile at an elevation of 2,300 m,
basins that are described in the following sections reveals great where it straddles the Tropic of Capricorn. The basin proper has a
variability in size, surface character, stratigraphy, structure, and surface area of approximately 3,000 km2, and the salt nucleus proper
chemistry. covers approximately 1,100 km2. The salar is bounded on the easternLithium Resources 603
Tertiary Esmeralda Formation 620
Tertiary Volcanic Tuff Li (ppm) 25 75 623 125 199 74 46 B
Pre-Tertiary Rocks 510
FX3
600 Lithium (ppm) in –2 µm Fraction
Well 530 500 Elevation (ft)
Playa Outline 5,500
Limit of High-Lithium Zone
350 T4
920 5,400
920 FX2 5,300
T5
800 5,200
N 600
T6
5,100
T3 T7
FX6 T1
5,000 T2
FX4
A Fault
1022
? Zone ?
1,000 ft
499 Vertical Exaggeration: 2X
1058
Figure 3. Lithium enrichment along Fault Zone 1, Clayton Valley,
1171 Nevada
449 498
A
410 B
1 mi
Figure 2. Lithium content (ppm) of surface sediment samples, Clay-
ton Valley, Nevada (A–B sampling location is in Figure 3)
side by Andean Cordillera and on the western side by the Cordillera
Domeyko (Figure 4).
The salt nucleus consists almost exclusively of a halite facies
with a development of very narrow marginal facies of sulfate and car-
bonate. The surface of the salar is extremely rugged because of
extensive development of polygonal cracks (Figure 5). It is similar in Figure 4. Aerial photo of Salar de Atacama (Chile) salt nucleus
many respects to the Devils Golf Course in Death Valley, California. and pond operating systems—SQL (southeast) and SQM (two pond
During the early exploration phase in 1975, access to the salar systems)
was limited to trails and a 37-km gravel road, so much of the
geochemical work was conducted by helicopter. Numerous roads
have since been built for the two brine operations. The Salar de
Atacama basin is a graben in a tectonically quite active area with
numerous fault scarps. The extensive thickness of salt in the basin
indicates that saturation with respect to sodium chloride was pre-
dominant during most of the subsidence history of the basin. No
beaches or algal reef complexes are present, which suggests desic-
cation from a much larger body of water. The ancestral chemical
system was probably very high in solutes. The source of the lithium
in the basin is volcanic in origin (Ide and Kunasz 1989). It enters
the basin from two principal directions. One is from the north
where the liquid from the El Tatio geothermal field (with lithium
concentrations of 47 ppm) discharges via the San Pedro River. The
other source is very likely from saline lakes in the Andean Cordil-
lera east of the salar. Structural interpretations by Frutos (1972)
suggest the presence of numerous east–west lineaments, which are
the conduits through which lithium-bearing solutions discharge into
the salar. Figure 5. Surface crust of Salar de Atacama (Chile)604 Industrial Minerals and Rocks
Table 1. Partial cation chemical analyses, wt %
Silver Peak, Salar de Atacama, Salar de Uyuni,
Cation Nevada Chile Bolivia
Li 0.023 0.14 0.025
K 0.53 1.87 0.62
Na 4.43 6.92 9.1
Mg 0.033 0.91 0.54
Mg:Li 1.5 6.6 21.5
imum surface dimension reaching 120 km (Figure 6). The surface
of the salar is smooth (Figure 7).
Meager subsurface data suggest that the salt crust is about 15
to 20 m thick. Extensive development of algal reefs some 75 m
above the present surface of the salar attests to the existence of a
Figure 6. Aerial view of Salar de Uyuni (Bolivia) much larger and less saline ancestral body of water—Lake
Minchin (quite reminiscent of the ancestral Lake Lahontan and the
present Great Salt Lake in Utah). The presence of several algal ter-
races suggests lowering of the lake level in several stages. The ulti-
mate stage represents saturation with respect to sodium chloride
and resulted in the precipitation of present crust. A sample col-
lected from a depth of 15 cm beneath the surface of the salt crust
by W.D. Carter (Ericksen, Vine, and Ballon 1978) gave a radiocar-
bon date of 3,520 ± 600 years, suggesting that salt precipitation
may have begun some 350,000 years ago. Comprehensive reports
on the studies conducted on the Salar at the request of the Bolivian
Government have been prepared by Ericksen, Vine, and Ballon
(1978) and by the Servicio Geologico de Bolivia (Ballivian and
Risacher 1981).
All three basins contain abnormal lithium concentrations. As
mentioned previously, the lithium must be attributed directly or
indirectly to volcanic geothermal activity of Recent or older age.
There is no doubt, however, that the strength recorded today in the
brine is the direct result of an intense concentration mechanism
resulting from natural solar evaporation.
Figure 7. Surface of the Salar de Uyuni (Bolivia) Table 1 shows some partial chemical analyses of the major
cations contained in the three brines. All analyses represent the
averages of several samples collected in each of the basins and
The deltaic sediments of the San Pedro River bind the salt early production averages from the well field for Silver Peak.
nucleus to the north. The surface of the salar is inaccessible The Salar de Atacama contains the highest lithium, potassium,
because of extensive polygonal cracking. Preliminary drilling by and magnesium concentrations (Table 1). Concentrations up to
CORFO (Corporacion de Fomento; a Chilean state development 7,000 ppm Li have been recorded in the Salar de Atacama brines.
agency) over various parts of the basin indicated a minimum thick- Several sources of lithium have been identified, but the most impor-
ness of 360 m of halite near the center of the basin, diminishing to tant was from the leaching of the volcanic rocks surrounding the
about 40 m near the southern margin. Drilling by the Hunt Oil salar. A second source was the weathering and leaching of exposed
Company indicates that the salt thickness may exceed 1,000 m. lacustrine sediments predating the formation of the salar. Geother-
Salt cores show that only the near-surface portion of the halite mal fluids such as those of the El Tatio (28 to 47 ppm Li) represent
crust has high porosity and permeability. A 10-km-long seismic a third source (Ide and Kunasz 1989). Of the three basins, however,
survey revealed that the highest porosity extends to a depth of 20 there is no question that the evaporation-concentration mechanism
to 25 m and that some additional lower-porosity halite may exist at was most intense for the Atacama Basin. Table 1 also indicates that
depths from 25 to 35 m. Below this depth, salt cores show com- ratios between various cations in the brine are different between the
plete recrystallization of the halite into a solid mass, devoid of any three basins, which strongly argues for different compositional
pores. The yield characteristics of the upper halite layer were inputs. The chemistry, specifically the Mg:Li ratios, also illustrates
determined by drilling and testing shallow wells to 30 m and 60 m. one of the important aspects controlling the production of lithium
The wells, pumped for 3 months at 64 L/sec, stabilized at draw- from different brines. In systems with high Mg:Li ratios, the phase
downs of 20 cm/sec and 7.9 m, respectively, corroborating that chemistry prevents the formation of lithium chloride brine unless
only the upper 30 m have a high transmissivity. the magnesium is removed at the start of the process. This has been
achieved in Clayton Valley (Barrett and O’Neill 1970) and at the
Salar de Uyuni, Bolivia Salar de Atacama. The exceedingly high Mg:Li ratio has prevented
The Salar de Uyuni is in southwestern Bolivia at an elevation of the development of the Salar de Uyuni (and the Great Salt lake) as
3,653 m. The salar represents an immense body of salt, with a max- an economic source of lithium.Lithium Resources 605
PRODUCTION FROM BRINE DEPOSITS
Historically, lithium chemicals and mineral concentrates were pro-
duced from pegmatites. The most important was the Kings Mountain
Belt of North Carolina, where the two major producers (Chemetall
Foote Corporation and FMC Lithium Division) mined and produced
lithium concentrates, mineral concentrate by-products, and lithium
chemicals.
In the early 1960s, Foote Mineral Company started develop-
ing the Silver Peak, Nevada, brine operation (Barrett and O’Neill
1970). Although the American Potash Corporation produced some ˚
23 15'
lithium as a by-product at Searles Lake, California (1938–1978),
Silver Peak was unique because it represented a primary source of
lithium carbonate from a brine deposit. Its uniqueness led to the
eyko
investigation and identification of lithium in numerous other salars
Dom
around the world and the eventual new production from Chile
(Salar de Atacama) and Argentina (Salar del Hombre Muerto).
Salar
de
Clayton Valley, Nevada Tropic of Capricorn
de ˚
23 30'
Foote Mineral Company traces its origins to A.E. Foote, who 2000
Cordillera
founded the company in 1876 as a purveyor of rare minerals. It 3000 Atacama
00
became a major producer of lithium chemicals when it acquired the 400
0
10
right to mine spodumene at Kings Mountain, North Carolina, in the
early 1950s. In the 1960s, Foote pioneered the production of lith-
2000
ium carbonate from brine with the opening of the Silver Peak plant
(Clayton Valley). It was acquired by Cyprus Minerals Company, 1000
then by Chemetall of Germany and more recently by Rockwood
Specialties. ˚
23 45'
The Clayton Valley salt marsh was first investigated during 0 5 10 15 20 25 km
the World War II effort to locate sources of strategic minerals, one
of which was potash. The salt marsh area was leased by the Ameri-
30 ˚ ˚
15 0
˚
can Potash Corp., which let the leases lapse. The leases were picked
Figure 8. Salar de Atacama—lithium, ppm
up by the Leprechaun Mining Company (Clyde Kegel), which con-
ducted some exploration on the subsurface brines and identified
lithium in addition to potassium. An agreement was later negotiated
with Foote Mineral Company, which developed the brines of the lithium carbonate; lithium metal ingots and foils for the primary
basin as a source of lithium carbonate (Barrett and O’Neill 1970). battery industry) at Kings Mountain, North Carolina.
In Clayton Valley, lithium-bearing brines occur in an asym-
metric, undrained structural depression filled with Quaternary sedi- Salar de Atacama, Chile
ments composed mainly of clay minerals, including hectorite, Two companies produce lithium carbonate and other salts from the
volcanic sands, and alluvial gravels, and saline minerals consisting brines of the Salar de Atacama: SCL, wholly owned by Chemetall
of gypsum and halite (Kunasz 1970). The brine that saturates the Foote, and SQM.
sediments is chemically simple. It is a concentrated sodium chlo- In the 1990s large-scale production of lithium carbonate
ride solution containing subordinate amounts of potassium and shifted from the United States to South America (Chile and Argen-
minor amounts of magnesium and calcium. The lithium concentra- tina). IIG made the first published reference on the occurrence of
tion is variable and decreases with pumping; the lithium concentra- lithium in Chile in 1969 when it undertook an extensive survey of
tion in the brine varies from 100 to 300 ppm Li. The dominant the Salar de Atacama. The institute published its findings in 1974
source of lithium has been a volcanic ash that extends across the (Moraga et al. 1974). Subsequent studies by CORFO showed that
basin. Exploration has identified additional aquifers and they sup- the salt nucleus contains a resource of 4.3 Mt of lithium (Penner
ply additional volumes of lithium-bearing brine. 1978). In April 1974, Foote Mineral Company (Cyprus Foote Min-
An extensive well field supplies the brine into some eral Company) verified the high lithium concentrations in the shal-
4,000 acres of solar evaporation ponds (Zampirro 2004). Over 12 to low brines below the saline crust. In January 1975, an agreement
18 months, concentration of the brine increases to 6,000 ppm Li was signed with CORFO to initiate a 4-year feasibility study to
through solar evaporation. When the lithium chloride reaches assess the potential of producing lithium carbonate from the brine.
optimum concentration, the liquid is pumped to a recovery plant The results of an exploration program based on test holes drilled on
and treated with soda ash, precipitating lithium carbonate, which 5-km centers revealed very high lithium concentrations (Figure 8)
is then filtrated out, dried, and shipped. Domestic production of over most of the salar (1,000–7,000 ppm Li).
lithium carbonate from brine is limited to Chemetall Foote’s oper- SCL, a subsidiary of Chemetall Foote, has been exploiting
ation in Nevada. At this time, the Silver Peak operation is one of the brines from the southern portion of the salar since 1984. The
the world’s leading producers of lithium hydroxide. Chemetall saturated brine is found 50 cm below the salt crust in a porous
Foote also produces normal and secondary butyl-lithium at its upper salt layer that reaches a thickness of about 30 m. It is
New Johnsonville, Tennessee, facility and a number of down- pumped via standard wells to a series of extensive, plastic-lined,
stream products (lithium chloride, bromide, and sulfate; U.S. solar evaporation ponds (Figure 4). The initial phase chemistry is
Pharmacopeia- [USP-] grade lithium carbonate and high-purity controlled by mixing brines from separate sectors of the salar to606 Industrial Minerals and Rocks
remove the magnesium and sulfate at the early stages of evapora- of lithium in these brine deposits range from 200 to 2,000 ppm and
tion. The final brine, concentrated to about 6% LiCl, is then trans- can be further concentrated using solar evaporation. Contributing to
ported by rail to the port city of Antofagasta, where it is converted efficient solar evaporation and concentration of the brines are the
to Li2CO3 by reaction with sodium carbonate. The combined SCL low rainfall and humidity, high winds and elevations, and relatively
production between the Silver Peak, Nevada, and the Salar de Ata- warm days in the area of the salars. When such conditions are
cama operations is approximately 20,500 tpy. SCL also harvests present, highly concentrated brines can be produced at reasonable
KCl as a by-product at the salar. cost and used as feedstock for a lithium carbonate plant.
Exploration by a number of companies over the northern por- While mining spodumene in North Carolina, FMC perfected
tion of the Salar de Atacama led to its development as a second and commercialized a selective purification process extracting
chemical production center. SQM, the Chilean nitrate producer, nearly pure lithium chloride from the salar brine with minimal pro-
acquired the development rights and started the production of cessing (North American Mineral News 1995). The Salar del Hom-
potassium chloride, potassium sulfate, and lithium carbonate in bre Muerto area also contains plentiful fresh water needed by the
1997. selective purification process. Selective purification uses low-cost
SQM is the world leader in specialty fertilizers, iodine, and raw materials housed in modular units. FMC has installed produc-
lithium carbonate. Created in 1968 as part of a plan to reorganize tion facilities for both lithium chloride and lithium carbonate from
the Chilean caliche (sodium nitrate) industry, SQM is today the the Salar del Hombre Muerto. Between 1999 and 2003, FMC pro-
lowest cost producer worldwide of potassium chloride, lithium car- duced an average of 4,800 tpy (Ober 2003), well short of the
bonate, potassium sulfate, and boric acid. Between 1994 and 1998 planned production capacity. With its market position in soda ash,
the company developed the largest nonmetallic project in Chile: the FMC planned to produce lithium carbonate at a competitive cost.
Salar de Atacama project. The three stages of the project required The company recently announced, however, that it will source its
an investment of US$300 million. The first stage was to build a carbonate requirements from Chile under a supply contract with
300,000-tpy potassium chloride plant, which currently produces SQM (Ober 2000). FMC also produces downstream lithium prod-
about 170,000 tpy KCl. The entire output is consumed internally, ucts at Bessemer City, North Carolina, and at Bayport, Texas.
supplying raw material to SQM’s potassium nitrate production. The
Potential Brine-Producing Districts
second stage was to produce lithium carbonate with a design capac-
ity of 23,000 tpy from brines obtained from the potassium chloride Argentina—Salar del Rincon and Others
production process. The last stage, begun in 1998, was the con- Equity-1 Resources of Australia has been involved in developing
struction of a potassium sulfate plant that now also produces boric Salar del Rincon. In addition to significant lithium, the brine con-
acid as a by-product. The company also produces boron chemicals. tains high concentrations of sulfates, resulting in a complex phase
SQM avoided the issue of the high magnesium concentration by chemistry that must be resolved before lithium can be economically
mixing brines of different compositions, resulting in a phase chem- recovered.
istry that led to the precipitation and subsequent harvesting of vari-
Qinghai Basin, People’s Republic of China
ous salts (sylvinite, potassium sulfate, and boric acid). The excess
residual brines are reinjected into the salar. Trucks carry the satu- As a result of the shift of lithium carbonate production from pegma-
rated solution of lithium chloride from the Salar de Atacama to the tite source to brines, the Chinese spent much effort to identify and
plant at the Salar del Carmen, east of Antofagasta, where it is puri- exploit brine deposits in the Qaidam Basin of northwestern China.
fied by removing the remaining boron and magnesium through A number of playas (salt lakes) have been identified. In the Golmud
extraction and filtering processes. Finally, the purified lithium brine Area, brines have been exploited for potash and Chinese research-
is reacted with sodium carbonate to produce lithium carbonate, ers have undertaken renewed efforts to produce lithium from the
which is filtered, washed, dried, and packed into different kinds of salt lakes of Tajinar and Yiliping, where high lithium concentra-
products. The production of lithium carbonate started at 22,000 tpy. tions have been recorded. The Mg:Li ratio is, however, very high
SQM now produces 40% of the world’s lithium carbonate. The and thus is a key to solving the process flowsheet (Peihua and
company has also started production of butyl-lithium at its Bayport, Pengxi 2000).
Texas, plant and has acquired LithChem, a producer of lithium car- The Qaidam Basin is in northwestern China’s Qinghai Prov-
bonate and lithium hydroxide. ince. Several playas have been explored, and some could quite pos-
sibly become centers of lithium chemical production. A group of
Salar del Hombre Muerto, Argentina scientists from the Qinghai Institute of Salt Lakes of the Chinese
Several lithium occurrences have been documented in the Argentin- Academy of Sciences has successfully solved the problem of sepa-
ian Altiplano (Poppi 1981). Discovered as a result of an Earth rating lithium from the brine solution, which contains a high con-
Resources Technology Satellite (ERTS) collaborative project centration of magnesium. The province will set up a company
(Nicolli et al. 1980), several salares (Hombre Muerto, Rincon, Pas- capable of producing 100 tpy of lithium chloride, near the Dong
tos Grandes, and others) were explored. In 1995, FMC Lithium Taijnar Lake. The Qaidam Basin has about 33 salt lakes with a
purchased the rights to the Salar del Hombre Muerto, a salar con- reported resource estimated at nearly 14 Mt of lithium chloride. At
taining high, uniform concentrations of lithium with low levels of present, the basin is China’s largest production base for potash fer-
other contaminants. The Salar del Hombre Muerto is in the high tilizer (People’s Daily 2000).
Andes at about 4,025 m above sea level, about 1,400 km northwest
Tibet
of Buenos Aires. The location is convenient to major rail lines and
seaports. Covering a smaller area than most salars of the region, it Lake Zabuye is one of 352 salt lakes on the Qinghai-Xizang
contains lithium brines at depths much greater than its neighbors. (Tibetan) Plateau. The lake lies in a closed basin at an elevation of
The site investigation involved core drilling, testing, sampling, and 4,421 m. The evaporation of these alkaline chloride-sulfate waters
hydrological studies. Reserves were estimated using geostatistical has led to a complex set of evaporitic minerals. Of importance is the
techniques and a three-dimensional flow model with coupled solute occurrence of zabuyelite, which precipitates from the lake waters as
transport, which indicate a reserve of 75 years. The concentrations natural lithium carbonate. The source of the rather extraordinaryLithium Resources 607
high levels of lithium (800 ppm) is most likely of geothermal origin, composed of eight discrete mineralogical zones comprising eco-
because the springs that feed the lake are abnormally high in lithium nomic minerals containing tantalum, lithium, cesium, and rubid-
(Holland et al. 1991). A recent announcement (China News 2005) ium, each occurring in separate zones. The various minerals are
indicated that 240 million yuans (US$29 million) have been invested spodumene, montebrasite, wodgonite, microlite, pollucite, lepidol-
in 2003 to build the Baiyin lithium carbonate plant in Lake Zabuye. ite, and feldspar. Jack McNutt discovered Bernic Lake in 1929, and
The plant capacity is reported to be 5,000 tpy of lithium carbonate. the area was first exploited for tin (Vanstone et al. 2000). Commer-
cial production began in 1969 with tantalum concentrates as the
PRODUCTION FROM PEGMATITE DISTRICTS major mineral. In 1984, Tanco began producing spodumene con-
Following the shift to lithium carbonate to Chile, the pegmatite- centrates, supplying Corning. Pollucite was also sold to the Soviets.
mining district of North Carolina was no longer able to compete Currently, the mine produces tantalum, cesium, and lithium.
economically. The two mining operations closed down, although Access is through both a decline and a shaft. Mining is carried
the sites continue to produce downstream lithium chemicals. Simi- out using the room-and-pillar method. Processing consists of crush-
larly, the two major producers no longer produce spodumene and ing to –12 mm, with tantalum and lithium ores stored separately,
other mineral concentrates. The slack was picked up by the three and pollucite and rubidium are collected into direct-sale stockpiles.
dominant producers in Canada (Tanco), Australia (Greenbushes), Tantalum is recovered via gravity separation and the concentrate is
and Zimbabwe (Bikita). sent directly to Cabot’s Boyertown, Pennsylvania, plant. Spo-
dumene is sent to a dense medium circuit where feldspar is
Australia removed. Further cleaning is achieved through a series of flotation
Spodumene is mined from a zoned pegmatite in the southwest of and gravity separations that remove tantalum, phosphates, mica,
Western Australia, approximately 300 km south of Perth and 80 km feldspars, and quartz. Separation produces an additional lithium
east of the Port of Bunbury. Sons of Gwalia acquired a 100% inter- concentrate, montebrasite, a lithium aluminum phosphate and spod-
est in the Greenbushes mine in 1998. ulite, obtained as the coarse fraction from the spodumene reject cir-
The Greenbushes pegmatite is the largest hard-rock tantalum cuit. The spodulite concentrate contains 5% Li2O. Magnetic
resource and the largest and highest-grade lithium mineral resource separation removes any extraneous iron. Pollucite is further pro-
in the world. The deposit is a zoned pegmatite with a strike length cessed by leaching to produce cesium chemicals (Hilliard 2002).
of more than 3 km. It contains zones of tantalite, spodumene,
sodium, and potassium feldspars with some overburden of very Zimbabwe
white, high-grade kaolin. The largest lithium-bearing area in Zimbabwe is the Bikita tin
Mining in the area has continued almost uninterrupted since fields, which is about 60 km east of Masvingo. Important mineral-
tin was first discovered in 1888. The spodumene deposit was identi- ized zones are in the Al Hayat, Bikita, and Southern sectors. The
fied in 1980 during the extensive drilling program for tantalum. By pegmatite is about 1,700 m long, and its width varies from 30 to
1983, initial development of the spodumene ore body commenced 70 m. It strikes north–northeast and dips from 14° to 45° east. The
and, by 1985, a 30,000-tpy spodumene concentrator was commis- pegmatite is asymmetrically zoned and contains a variety of com-
sioned. This was later increased to 100,000 tpy capacity in 1993– mercially important lithium minerals as well as beryl and pollucite.
1994 and again to 150,000 tpy capacity in 1996–1997. The ore Bikita Minerals (controlled by AMZIM Minerals, a company in the
reserve and resource are >13 Mt, that is, sufficient to supply high- United Kingdom) produces standard petalite, low-alkali petalite,
grade products for several decades. container-glass petalite, and spodumene concentrate.
The Minerals Processing Plant, constructed in 1980 as a tan- Other minor lithium-bearing occurrences are in the Wankie,
talum pilot plant, was converted to the Lithium Minerals Process- Salisbury, Umtali, Mtoko, Insizia, Matobo, and Mazoe districts
ing Plant in 1983. The plant was expanded several times, the latest (Toombs 1962).
in 1995, to meet increased demand for spodumene. This plant lib- Production of lithium minerals increased from 18,064 t in
erates and recovers the spodumene into several spodumene miner- 1993 to 49,883 t in 1997 (Mobbs 1998) but declined to 33,000 t in
als by milling, screening, flotation, gravity, and magnetic 2002 (Cockley 2002).
separation processes to meet the requirements of the various prod-
Other Producing Regions
uct applications.
The Greenbushes operation produces about 60,000 tpy of spo- Russian Federation
dumene concentrates. It supplies about 60% of the world market. The Russian Federation produces spodumene and other mineral
The highest quality concentrate has a grade of 7.5% Li2O. The concentrates at the Pervomaisky mine, southeast of Chita. The spo-
company also produces several other concentrates. A chemical dumene occurs in unzoned pegmatites that intrude amphibolites,
plant was constructed but was mothballed after a fall in the world reminiscent of the Kings Mountain system. The narrower veins are
price of lithium (ACTED 1997). not mined selectively, which requires belt sorting to remove the
host rock before processing and production of spodumene concen-
Canada trates and other minerals recovered. The concentrates are railed
Tantalum Mining Corporation of Canada is part of Cabot Specialty more than 2,000 km to processing facilities in Krasnoyarsk, where
Fluids, a division of Cabot Corporation, Boston, Massachusetts. It the spodumene is converted to lithium hydroxide and metal and
produces spodumene from a zoned pegmatite and operates a con- then further transported to Novosibirsk, where lithium carbonate
centrating plant at Bernic Lake, Manitoba, Canada. The site is and other chemicals are produced (production data unavailable).
about 130 km northeast of Winnipeg. Low-cost carbonate production from Chile shut down the plant.
The Bernic Lake pegmatite is one of a number of subhorizon- Historically, the former Soviet Union obtained its spodumene
tal pegmatite sheets in the Bird River greenstone belt within the concentrates from the People’s Republic of China from a mine in
Superior geological province in the Canadian Shield. It was formed the Altai Mountains (near Fuyun) in Sinkiang Province. When the
during the Kenoran Orogeny of the Late Archean age and is Soviets realized that they were going to be ousted, they began an
approximately 2.5 billion years old. Internally, the pegmatite is intensive development program of the pegmatite field identified608 Industrial Minerals and Rocks
southeast of Chita and built a self-contained infrastructure at Pervo- It is a company certified in the recycling of various lithium battery
maisky. After the 1959 events, China took control of the Sinkiang types as well as other metal types (Toxco 2003).
region, and the Soviets were left to their own means. Pervomaisky In 1995, Toxco won a contract for the purchase of 68 million
became the source of the spodumene for the Soviet military-indus- pounds of depleted lithium hydroxide monohydrate, used in the
trial complex. 1950s and 1960s at Oak Ridge, Tennessee, for the production of
lithium isotopes for use in the production of thermonuclear weap-
People’s Republic of China ons (Frank 1995). LithChem International, a subsidiary of Toxco
The People’s Republic of China produces lithium and other mineral that produces lithium carbonate and lithium hydroxide in Balti-
concentrates (beryl, lepidolite, high-purity quartz) from a mine in more, Maryland, was purchased by Soquimich, the Chilean fertil-
the Altai Mountains in northwestern China. The lithium concen- izer and lithium producer. Another subsidiary, Ozark Fluorine
trates are trucked some 600 km to Urumqi, the capitol of Sinkiang Specialties, produces hydrofluoric acid, which is converted to lith-
Province, where a processing plant produced lithium hydroxide ium hexafluorophosphate, high-purity lithium fluoride, and other
using the old Foote Mineral lime–spodumene process. With the electrolytes used in lithium batteries at its Tulsa, Oklahoma, plant.
recent information on the production of lithium carbonate, it must
be assumed that the plant has been partially converted to the acid- Potential Producing Districts
roast process. Low-cost lithium carbonate from Chile may have People’s Republic of China
shut the plant down (Ober 2000). The Jiajika pegmatite in Sichuan Province was discovered in 1959
and explored in the period 1959–1992. It is the largest lithium min-
Minor Producing Districts eral deposit in Asia, with reserves, as defined by China, of 1.03 Mt
Argentina of 1.28% Li2O. The deposit is easily accessible by existing
In Argentina, lithium-bearing pegmatites occur in the western part infrastructure.
of the Sierras Pampaneas region, which includes the productive dis- The Lushi pegmatite field, in Henan Province, extends more
tricts of San Luis, Cordoba, and Catamarca. The pegmatites are than 100 km2, and numerous veins have been discovered.
zoned and contain spodumene. The reserves, considered to be Sterling Group Ventures of Australia, through a holding sub-
small, total about 18 kt as spodumene (Angelleli and Rinaldi 1963, sidiary, has signed two agreements to develop the Jiajika and Lushi
1965). deposits. The joint venture is expected to operate the Jiajika deposit
with an initial capacity of 240,000 tpy and produce 47,320 tpy of
Brazil concentrates (6.09% Li2O).
In Brazil, lithium-bearing pegmatites occur in the Minas Gerais and On April 10, 2004, Sterling entered into a formal joint-venture
in the northeastern part of the country, which includes the states of agreement with Lushi Guanpo Minerals Development (Lushi) of
Paraiba, Rio Grande do Norte, and Ceara (Afghouni 1978). Henan Province of China to bring the project into production and
In the state of Minas Gerais, near Aracuai, several pegmatites earn 90% of the interest of the project. According to Chinese
have been exploited on a sporadic basis. The pegmatites, which geological brigades, the property is estimated to contain about
carry spodumene, amblygonite, petalite, and lepidolite, have been 200,000 t Li2O grading 1%. The concession covers about 100 km2
traditionally mined for cassiterite, tantalite, and beryl, and lithium and has large potential to increase the resources of lithium.
minerals have been sporadically recovered. As a result of an
increase in demand for lithium minerals (petalite), exploration Democratic Republic of the Congo
activities resulted in the discovery of important petalite pegmatites, Probably the largest hard-rock lithium resources in the world are in
reported to contain 100 kt of petalite grading 2% Li. Spodumene the Manono and Kittolo in the Democratic Republic of the Congo.
reserves have been estimated at 300 kt, whereas lepidolite reserves Currently Congo-Etain mines only cassiterite and columbite from
are considered to be nearly exhausted. the Manono pegmatite, which is 5 km long and from 120 to 425 m
The most important producer of lithium minerals is Arqueana wide. The adjoining Kittolo pegmatite has similar dimensions.
de Minerios e Metais (Sao Paulo). The company mines spodumene, Although the pegmatites are apparently zoned (Varlamoff 1954),
petalite, lepidolite, amblygonite, beryl, and cassiterite from the peg- their dimensions imply spodumene reserves that dwarf the cur-
matite bodies near Aracuai in Minas Gerais. The company also sup- rently known world reserves. The deposit may not have an eco-
plies spodumene concentrates to Companhia Brasileira do Litio nomic value for years, however, because of very poor transportation
(CBL), a small producer of lithium carbonate and lithium hydrox- facilities. The deposit is about 2,200 km from the Angolan port of
ide (Ober 2003). The processing facilities have been constructed in Lobito.
an economically depressed region several hundred kilometers north
of the mining district to benefit from government incentives. The Canada
plant is estimated to produce about 1,500 t of lithium carbonate Avalon Ventures was developing the Separation Rapids rare-metals
(K. Afghouni, personal communication). project in northwestern Ontario not far from the Tanco operation.
Avalon was increasing the capacity of its flotation pilot plant to be
Other Areas able to produce large enough volumes to provide potential custom-
Lithium minerals are also produced in Portugal (lepidolite), Spain ers with enough high-grade petalite concentrate for sampling.
(lepidolite), and Argentina (spodumene and amblygonite). AMZIM Minerals, the offshore holding company of Bikita
Minerals, the Zimbabwe petalite producer, planned to produce pet-
NEW PRODUCERS alite at a site owned by Emerald Fields Resource Corp., a Canadian
Toxco company, from the same pegmatite body between the Tanco and
Toxco, a California company, offers any organization within the Avalon operations. This operation was named the Big Mack. If all
U.S. federal government a preapproved battery recycling contract. the tests turned out as expected, construction of a plant with an ini-
tial production capacity of 15,000 tpy of petalite concentrate was toYou can also read
