Sierra LeoneBack in Business
A country rich in natural resources
Rutile and bauxite operations have started
Diamond exploration has begun at Kono
SPECIAL PUBLICATION
LeoneLeoneLeone
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2 Mining Journal special publication
SIERRA LEONE
MINISTRY OF MINERAL RESOURCESMinister’s O� ceMohamed S Deen, Minister of Mineral ResourcesYouyi BuildingBrook� eldsFreetownTel: +232 22 240142 / 241147Fax: +232 22 242107 E-mail: [email protected]
Permanent SecretaryS G PessimaYouyi BuildingBrook� eldsFreetownTel: +232 22 240172Fax: +232 22 240172
Director of MinesAlimamy R WurieYouyi BuildingBrook� eldsFreetownTel: +232 22 240420 / 240467Fax: +232 22 240467E-mail: [email protected] á[email protected]
Deputy Director of MinesUsman Boie KamaraYouyi BuildingBrook� eldsFreetownTel: +232 22 240574Fax: +232 22 240574E-mail: [email protected]
Gold and Diamond DivisionL Ndola-Myers, CommissionerE Tucker, Deputy CommissionerBank of Sierra Leone BuildingCharlotte StreetFreetown Tel: +232 22 222600Fax: + 232 22 229064E-mail: [email protected]
Director Geological SurveyMohamed B MansarayNew EnglandBrook� eldsFreetownTel: +232 22 240740Fax: +232 22 241936
Deputy Director Geological SurveyTyril GouldsonNew EnglandBrook� eldsFreetownTel: +232 22 240682Fax: +232 22 241936
Sierra Leone Chamber of CommerceGuma BuildingLamina Sankoh StreetTel: +232 22 226305Fax: +232 22 220085E-mail: [email protected]
KEY CONTACTS
Artisanal Mining on the Ba� n River, Sandor Chiefdom, Sierra LeoneXXSandor Chiefdom, Sierra LeoneXXSandor Chiefdom, Sierra Leone
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Message from the Minister of Mineral Resources
On behalf of His Excellency Alhaji Dr Ahmad Tejan Kabbah, President of the Republic of Sierra Leone, the Government and People of Sierra Leone, I want to take this opportunity, once again to welcome you and your investment into the mining sector of this beautiful and friendly country. The country is undergoing a major transformation
in the economic landscape and the mining industry is providing one of the major engines of growth. Opportunities abound in the � elds of prospecting, exploration and mining for a variety of minerals as illustrated in this supplement.
We look forward to your early entry into this vibrant sector.
Alhaji Mohamed S DeenMinister of Mineral ResourcesSierra Leone
CONTENTSReady to move forward 3Geological map of Sierra Leone 6Resource potential 9
Published by Mining Journal, London, August 2006
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Mining Journal special publication 3
Ready to move forward
SIERRA LEONE
SIERRA LEONE became an Independent Republic in 1961, having previously been a British Protector-ate since 1896 and under
British administration since 1787. Freetown, the capital of this small West African state, derives its name from the freed slaves who were resettled there in the late 18th century. Their descendants have since played an important part in Sierra Leone’s culture and economy.
The country is slightly smaller than Scotland and a little larger than Sri Lanka. In the African context, this is a distinct advantage, with no vast distances to consider as regards project infrastructure. Also, it bene� ts from an Atlantic seaboard and good natural ports, with nowhere in the country more than 300 km from the coast. And, despite its modest size, Sierra Leone is richly endowed with natural resources.
Ample rainfall and fertile soils ensure that it is capa-ble of producing a wide variety of agricultural products, and its diverse mineral resource base, recognised very
early by the Geological Survey of Sierra Leone in the 1920s and 1930s, has supported a vibrant mining sector since that time. In the post-independence days of the 1960s, for example, dia-monds and iron ore were mainstays of the economy and subsequently bauxite and rutile were added to the list.
Since the last supplement produced by Mining Journal (in February 2003), Mining Journal (in February 2003), Mining Journalthere has been tremendous progress
in Sierra Leone’s mining industry. For example, the country’s rutile and bauxite operations have restarted, and diamond exploration and mining (at Kono) is in full swing. Gold exploration has quickened, and metal output is improving.
This supplement demonstrates that Sierra Leone is fully back in business, that there are abundant opportu-nities in the minerals sector and that the government is making every e� ort to encourage foreign investors.
GEOGRAPHYSierra Leone is situated on the west coast of Africa between latitudes 10° and 12° west and longitudes 7°
and 10° north, and covers an area of some 71,620 km2. To the south and southwest its Atlantic coastline extends for almost 400 km. The country shares its north and northeastern border with the Republic of Guinea, and its southeastern border with Liberia.
Sierra Leone possesses a tropical and humid climate, with a clearly de� ned rainy season. Annual rainfall averages 380 cm (150 inches) in Freetown, decreasing inland to 200 cm (80 inches) in the north of the country. Most of the rain falls between July and September, but as the period is preceded and succeeded by thunder-storms, the wet season is extended from May to Octo-ber. During the remainder of the year, the dry season, rainfall is scanty. There are mangrove swamps along the coast but most of the country is covered with dense secondary forest or bush, and over large areas the land surface comprises residual laterite, or detrital material. The country possesses numerous streams and rivers.
Broadly speaking, the western half of Sierra Leone comprises a large plain, while the eastern half consists of a number of elevated plateaux rising to a maxi-mum height of 1,950 m (6,390 ft) above sea-level at Bintumani in the Loma Mountains. The plain comprises a 40 km-wide coastal belt composed of marine or
Sierra Leone’s abundant resources mean that mining will play a vital role in the country’s future
since played an important part in Sierra Leone’s culture
early by the Geological Survey of Sierra Leone in the 1920s and 1930s, has supported a vibrant mining sector since that time. In the post-independence days of the 1960s, for example, dia-monds and iron ore were mainstays of the economy and subsequently bauxite and rutile were added to the list.
by there has been tremendous progress
in Sierra Leone’s mining industry. For example, the
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Members of Sierra Leone Diamond Co alluvial diamond exploration team
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Mining Journal special publication4 Mining Journal special publication
SIERRA LEONE
deltaic sediments running parallel to the coast, and a continental belt stretching some 95 km inland from the coastal plain, underlain by rocks of the old continental land mass.
The surface of the plain is gently undulating and rises towards the east to about 120 -150 m above sea-level at the base of the plateau escarpment. It is characterised by numerous isolated hills and hill ranges, or monadnocks, remnants of an earlier plateau. The layered igneous intrusion underlying the Freetown Peninsula forms a well-forested, highly dissected mountainous area andwell-forested, highly dissected mountainous area andwell-forested, highlyis one of the most distinctive physical features on the west coast of Africa.
The eastern half of Sierra Leone consists of elevated plateau country lying between 300 m and 600 m above sea-level. Other plateaux and plateau remnants rise above this general level, especially near the eastern frontier with Guinea. The western margin of the plateau is more or less clearly de� ned by an eroded escarpment, and the existing scarp face is � anked by parallel hill ranges and by numerous residual domes and inselbergs of granite. Most of the rivers descend from the plateau to the coastal plain in a series of rapids and waterfalls.
The estimated population of Sierra Leone in 2004 was 4.98 million and an overall population density of 70 people/km2. Freetown, the capital, is the largest city and other major towns include Kenema, Bo and Makeni.
There are about 18 ethnic groups exhibiting similar cultural features. These include a system of govern-ment based on chieftaincies and patrilineal descent, subsistence farming and secret societies. The Mende, found in the east and south, and the Temne, in the north, are the two largest groups. Other major groups include the Limba, Kuranko, Susu, Yalunka, and Loko in the north; the Kono and Kissi in the east; and the Sherbro, in the southwest. Minor groups include the coastal Bullom, Vai and Krim, and the Fulani and Malinke (Madingo). The Creoles, descendants of freed blacks, arrived in the 19th century and are found mainly in the western area and Freetown. There has been much intermarriage between ethnic groups.
Islam is practiced by over 70% of the population, and Christianity by about 10%. The remainder follow tradi-tional beliefs. English is the o� cial language, although its regular use is limited to a literate minority, Mende is the principal vernacular in the east and south, and Temne in the north. Krio (English-based Creole, spoken by the descendants of freed slaves) is a lingua franca and a � rst language for 10% of the population but is understood by 95%.
GEOLOGICAL OVERVIEWMost of the country is underlain by rocks of Precambrian age (Archaean and Proterozoic) with a coastal strip about 50 km in width comprising marine and estuarine sediments of Tertiary and Quaternary to recent age. The Precambrian (mainly Archaean) outcrops over about 75% of the country and typically comprises granite-green-stone terrain. It represents parts of ancient continental nuclei located on the edge of the West African Craton. Regional reconnaissance mapping indicates that the Archaean basement can be subdivided into infracrustal rocks (gneisses and granitoids); supracrustal rocks (containing greenstone belts); and basic and ultrabasic igneous intrusions.
The infracrustal gneisses and granitoids were formed
and reworked during two major orogenic cycles, an older Leonean episode (~2,950-3,200 Ma) and a younger Liberian episode (~2700 Ma).
The Leonean orogenic episode commenced with the intrusion of a basic igneous suite (the Pre-Leonean amphibolites) and by the formation of a greenstone belt represented by the Loko Group which is now deeply eroded. The Loko Group comprises amphibo-lites, silimanite quartzites and ironstones. It appears to have formed on a gneiss/granitoid basement in which
Founded by Algy Clu� in 2003, Clu� Gold plc is focused on the identi� cation, acquisition and development of gold deposits in Africa that are amenable to open-pit mining and low-cost produc-tion techniques. The company, which was admitted to AIM in December 2004, has assembled a portfolio of mineral interests in Africa, and include options to purchase the gold assets of Ridge Mining (formerly known as Clu� Mining plc), which was established by Mr Clu� in 1996.
The company’s assets include Sierra Leone’s Baomahun gold project, which is held through Clu� Gold UK Ltd and Clu� Gold (SL) Ltd.
The group is earning a 60% interest in the 137 km2
Baomahun licence area from Winston Mines (based on it spending US$5 million on exploration or completing a bankable feasibility study). The deposit is located 180 km east of the capital, Freetown. The geological setting is similar to Lake Victoria gold� elds in Tanzania, and a total of � ve zones of mineralisation have been identi� ed, covering a combined strike length of 3.4 km.
The company has successfully completed a 4,600 m core-drilling programme on three zones within the southern sector of the Baomahun licence. Independent consultant SRK has completed a resource estimate (in accordance with the JORC code) of some 4.5 Mt with an average gold grade of 3.6 g/t (representing just over 0.5 Moz). This is twice the amount estimated when the company was admitted to AIM.
Each of the three zones (Eastern, Western and Central) drilled to date remain open at depth and represent less than 25% of the prospective geological corridor on the Baomahun licence. Airborne geophysi-cal surveys conducted in January 2005 also identi� ed strike continuity of the banded iron formation.
CLUFF GOLD PLC
London-based Target Resources plc is focused on alluvial diamond and gold mining in the Kono District of Sierra Leone. The company, which operates through its wholly-owned subsidiary Milestone Trading Ltd, is seeking a listing on the AIM market in London.
Kono was historically the most lucrative diamond-mining district in Sierra Leone, with various structur-ally-controlled drainage channels � owing towards the Ba� River, which in turn drains into the Sewa River. The Tongo and Kono � elds, in which Milestone is active, are characterised by the presence of kimberlitic dykes and pipes, as well as river and alluvial deposits.
The Upper and Middle Sewa River Valley consists of a relatively narrow gorge that ranges from a few hun-dred metres to roughly 2 km in width, with diamonds occurring in both the river itself and in various terrace gravels along the riverbanks. The Lower Sewa River � ows on the coastal plain elevation but, although diamond deposits do occur in this area, the average stone size is much smaller.
An exploration scheme is in place over the company’s total property area of some 1,500 ha, and US$11.4 million has already been invested by Milestone in acquiring and setting up a process plant and ancillary equipment to treat up to 50 t/h of diamondiferous gravel.
This plant is already treating gravel in the Bagbema area of the Sandoh chiefdom, and additional earth-moving equipment is being brought in by the South African subcontractor Three Captains Mining Ltd in order eventually to treat 12.0 Mt/y. Further leases are currently being secured in two other chiefdoms (Nimi-yama and Nimikoro), and joint venture agreements with the chiefdoms are in place.
Sandoh chiefdom: Target is working, in co-opera-tion with local chiefdoms, on a 6.5 km2 site in the Bagbema-Fenima area.
Nimiyama chiefdom: A Heads of Agreement was signed in May 2005 with the chiefdom, followed by a full JV in December. Nimiyama lies south of the Sandoh chiefdom, on the south side of the Ba� River. The intention is to mine about 600 ha, starting with the area just across the river from Bagbema.
Nimikoro chiefdom: A full JV was signed last December with the chiefdom, and the intention is to mine about 400 ha of virgin alluvial land. In addition, a licence exists to mine the No5 tailing dump, and underlying virgin gravels, in this chiefdom. The 2.5 Mt dump was generated by large-scale alluvial mining operations by Sierra Leone Selection Trust in the 1960s and 1970s. The material has an estimated grade of about 2 ct/100 t.
Based on an estimate by consultant SRK that 40% of the total licence area is diamondiferous, the company calculates its resource potential at 19.7 Mt grading an average of 15 ct/100 t, yielding 2.9 Mct. In the 12 months to end-February 2006, Milestone produced 18,800 t at 21 ct/100 t, for almost 4,000 ct at an average received price of US$473/ct. Using its new contractor, the company plans to produce 288,000 ct/y by 2008.
TARGET RESOURCES PLC
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Mining Journal special publication 5
SIERRA LEONE
several granitoid bodies related to an earlier plutonic-orogenic episode have been distinguished mainly in the northern part of the country. Only the main deformational phase of the Leonean orogenic episode which resulted in folds and fabrics trending east-west has been distinguished. Minor gold and cassiterite min-eralisation associated with portions of the Loko Group is probably related to a late Leonean granitisation event which accompanied the formation of major shear zones in the craton.
Other volcano-sedimentary sequences are preserved within the granites, gneisses and migmatites. Highly folded greenstone belts predominate in the north and central Sierra Leone. In the southeast, the metamorphic facies increases, � rst with the Kambui Schists and � nally with the Mano-Moa Granulites.
Greenstone belts of the Kambui Supergroup are believed to have been deposited upon a post-Leonean basement and accompanies by basic to ultrabasic intrusives. The Kambui Supergroup includes most of the schist belts exposed in the Sula Mountains and the Kangari, Kambui, Nimini and Gori Hills; the Marampa Group; and the two small greenstone belts of Serekolia and Sankarama in the northeast. These greenstone belts comprise a lower volcanic unit composed of ultra-basic lavas and basic lavas with pillow layers, overlain by a sedimentary unit comprising tu� s, pelitic and psammitic sediments, with conglomerate layers and ironstone bands. The greenstone belts are the principal hosts of the gold mineralisation of the country.
Other associated mineral deposits include molybde-nite, columbite-tantalite and chromite. The Marampa Group, bounded on its eastern margin by a tectonic contact, is important for its iron-ore deposits and forms the upper part of the Kambui Group.
Late Liberian granitoids, marginal to, and within, the Kambui Supergroup, are associated with important zones of shearing and deformation where gold, sulphide and molybdenite mineralisation has been concentrated.
The Rokel-Kasila Zone bounds the main part of the West African Craton on its west and southwestern margin in Sierra Leone, and appears to form part of a north-south orogenic belt. Within this belt, the Marampa Group appears to represent some of the oldest rocks. The Kasila Group, also considered to be part of the Kambui Supergroup, comprises a high-grade series of granulites, consisting of garnet, hypersthene and hornblende gneisses, quartzites and associated migmatites. Where eroded, signi� cant secondary deposition of titanium minerals have formed from this unit. The Kasila Group also contains bauxite.
A late Precambrian to Cambrian sedimentary and volcanic assemblage, the Rokel River Group, was deposited unconformably on a basement complex.
Deposition was probably in a fault-bounded basin of the intracratonic type along the line of the Rokel-Kasila Group following the formation of the tectonic zone at the end of the Liberian or during the Eburnean Orogeny. The Rokel River Group and the Kasila Group to the west were deformed during the Rokelide orogenic episode (~550 Ma). Deformation increased in intensity westwards.
The Saionya Scarp Group forms a small ingression into Sierra Leone in the northwest of the country, and is composed of horizontally-bedded arkoses, grits and shales with intruded dolerite sills. The group appears to
belong to that part of the Gres Horizontaux of Guinea which has been classi� ed as Ordovi-cian, based on the discovery of the graptolites Monograptus riccartonensis and Monograptus priodon in shales near Telimele. In Sierra Leone, the Saionya Scarp Group rests unconform-ably on The Rokel River Group.
Dolerite intrusions are com-mon as dykes trending mainly east-west within the basement complex, and as extensive sills above the Rokel River Group. Kimberlite dykes and pipes fol-low a similar pattern in the east of the country and could also be present in the north and west.
The Freetown igneous complex forms an intrusive body on the coast, with arcuate outcrop concave towards the west. It is composed of a layered complex of gabbro, norite, troctolite and anorthosite. Platinum occurs in the gravels of many of the streams that cut the outcrops of anorthosite and anorthositic gabbro in the noritic gabbro complex of the Freetown Peninsula. The relation of this complex with the other units is obscured by the coastal veneer of Tertiary sediments of the Bullom Group which lies unconformably on the basement.
Tertiary and more recent weathering has led to lateritisation across a large part of Sierra Leone, a� ecting mainly the greenstone belts and the extensive dolerite intrusions. The bauxite deposits formed within the Kasila Group are a result of this weathering process.
MINING AND THE ECONOMYThe economy of Sierra Leone is based on agriculture and mining. The bulk of the population is engaged in subsistence farming. Plantation agriculture is signi� cant only in certain parts of the country. Mining has been of vital importance to the country’s export trade. In the late 1980s, budget � gures showed annual revenue from mining of about US$98.5 million. The onset of civil war during the 1990s seriously disrupted the country’s min-ing sector but, following the end of the war in 2002 and the re-establishment of law and order, there is now every hope that the mining sector will once again provide a vital cog in the economy and that many of the known but unexploited mineral deposits will be developed.
Sierra Leone Diamond Co Exploration Ltd (SLDC) is a Sierra Leone-based company which has been actively prospecting for diamonds and other minerals for a little over two years. Currently the company holds 42,900 km2 in its licence portfolio. Although the primary thrust of the exploration programme is centred on discovery of primary diamond sources, work is also being carried out on iron ore, gold and other commodities. Despite the di� cult working conditions the majority of the area being either swamp or heavily forested, over 6,000 samples have been taken to date.
The company has established a heavy mineral laboratory and washing station at Bo, and has four external camps, where its � eld crews are based, at Kamakwie, Lunsar, Yengama and Sumbuya. Field work has largely been based around the collection of reconnaissance stream samples.
These samples are sent to the custom-built laboratory in Bo. The � ner fractions of each sample are dispatched for � nal sorting in South Africa. Visually positive kimberlitic indicator minerals are then extracted for mounting and micro-probing in order to determine the mineral chemistry and prospectivity. Laboratory results are captured onto the company’s custom-designed sample database. This is the � rst time that such a systematic sampling programme for kimberlites has been conducted across this highly prospective country.
SLDC also commissioned the � rst High Resolution Aero Magnetic (HRAM) survey to be conducted in Sierra Leone. Data acquisition is now complete, with over 319,000 line kilometres of data having been collected, and interpretation is underway.
This work has already led to the discovery of three new diamond occurrences in the east of the country. Each of these sites has now been bulk sampled, with encouraging results.
In addition to ongoing exploration activity, SLDC has been granted a ten-year mining lease (with options to renew) for the extraction of alluvial diamond deposits in the Kono region. The lease, extending over a 160 km2 area of the Ba� river and terraces, is spread across the Nimiyama, Nimikor, Sandor and Kamara Chiefdoms.
SLDC has acquired an earth-moving � eet and a DMS plant capable of processing 2.0 Mt/y of alluvial gravels. This plant has been upgraded, and further investment made in a newly-commissioned x-ray � nal-recovery unit.
SLDC has progressed with its mining operation in the Tefeya area both in the River Ba� and the associated lower terraces. The adoption of a � exible mining approach and improvement in processing technology allows for the e� cient processing of diamond from basal river gravels, top river gravels and lower terrace gravels.
A demonstration of the commitment of SLDC to developing the mineral resource within the mining lease is the purchase of an additional ten earth-moving vehicles, and the ordering of an additional DMS plant with a capacity to process 1.5 Mt/y of alluvial gravels, providing the company with a combined processing capacity of 3.5 Mt/y by the end of 2006.
The presence of SLDC in the Kono region has had a demonstrable impact on the local community both in terms of improvement in infrastructure and contributing to economic development. SLDC works collaboratively with lo-cal communities and, where practical, makes use of its equipment and resources to assist in infrastructure projects, such as the creation of communal facilities, maintaining water pumps for ongoing provision of potable water and improving local access routes through road resurfacing and bridge building.
With its exploration and mining operations, SLDC provides legitimate permanent employment opportunities for over 500 skilled and semi-skilled Sierra Leonean citizens with additional temporary opportunities for many more. Initiatives are being put in place to reduce the requirement on external resources (currently around 80 expatriate sta� ) and so increase the percentage of local sta� .
SLDC
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Artisanal Mining on the Ba� n River, Sandor Chiefdom, Sierra LeoneXXSandor Chiefdom, Sierra LeoneXXSandor Chiefdom, Sierra Leone
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SIERR
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Mining Journal special publicaiton
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pro
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)
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vium
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phib
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mat
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ocks
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ic g
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qua
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te, f
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nded
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e (
)
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phyr
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stic
ban
ded
gnei
ss, p
yrox
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eiss
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mat
itic
gnei
ss, g
rani
toid
; myl
onite
(
)
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phib
olite
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phib
olite
, qua
rtzi
te, b
ande
d iro
nsto
ne
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mat
itic
gnei
ss a
nd g
rani
toid
Q Tb Jd Jf Ow
Om
Prt
m
Lmr
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Lb Lg Lkm
Lkt
LA
n
Lam LM
Lm
g
LG
PLa PLI
PLg
London, July 2006London, July 2006London, July 2006London, July 2006London, July 2006London, July 2006 Mining Journal special publicaiton 777
NNLI
TH
OLO
GY
Allu
vium
, bea
ch s
and,
etc
.
San
d, c
lay,
cla
y sa
nd, l
igni
te, e
tc.
Dol
erite
Dun
ite, g
abbr
o, tr
octo
lite,
oliv
ine
gabb
ro,
leuc
ogab
bro,
ano
rtho
site
Lam
inat
ed a
rgill
ite w
ith r
hyth
mite
s
Sha
le, a
rkos
ic s
ands
tone
, san
dsto
ne, c
ongl
omer
ate
Bas
ic in
trus
ive
Var
iega
ted
shal
e, la
min
ated
silt
ston
e,or
thoq
uart
zite
, sub
arko
se, a
rkos
e
Gre
y m
udst
one
and
shal
e, o
ccas
iona
l bed
s of
gre
ycl
ayey
silt
ston
e, fi
ne−g
rain
ed s
ands
tone
, lam
inat
edsi
lty s
hale
And
esiti
c la
va, s
pilit
ic b
asal
t, da
cite
, dac
itic
tuff
Pur
ple
and
grey
sha
le w
ith in
terb
edde
dqu
artz
wac
ke b
ands
.
Gre
y sh
ale
inte
rbed
ded
with
qua
rtzi
te, a
rkos
e,su
bark
ose,
con
glom
erat
e (
)
Pel
itic,
sem
i−pel
itic
and
psam
miti
c m
etas
edim
ents
;ha
emat
ite, q
uart
zite
and
spe
cula
rite
schi
st; B
ande
dIr
on F
orm
atio
n (
)
Mas
sive
and
ban
ded
met
a−an
desi
te, u
ltrab
asic
lava
, pill
ow la
va
Nep
helin
e sy
enite
, sye
nite
, alk
ali g
rani
te
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tite
gran
ite, p
orph
yrob
last
ic g
rani
te, g
rani
toid
Qua
rtzo
−fel
dspa
thic
gne
iss,
coa
rse
amph
ibol
ite,
garn
etife
rous
gne
iss,
lava
Hyp
erst
hene
gne
iss
with
feld
spat
hic
band
s, o
livin
e−be
arin
g m
etag
abbr
o
Ano
rtho
site
, met
agab
bro
Am
phib
olite
, cor
onite
Mig
mat
ites,
hyb
rid r
ocks
Maf
ic g
ranu
lite;
qua
rtzi
te, f
erru
gino
us q
uart
zite
,ba
nded
iron
ston
e (
)
Por
phyr
obla
stic
ban
ded
gnei
ss, p
yrox
ene
auge
ngn
eiss
, mig
mat
itic
gnei
ss, g
rani
toid
; myl
onite
(
)
Am
phib
olite
Am
phib
olite
, qua
rtzi
te, b
ande
d iro
nsto
ne
Mig
mat
itic
gnei
ss a
nd g
rani
toid
Q Tb Jd Jf Ow
Om
Prt
m
Lmr
Lmm
Lb Lg Lkm
Lkt
LA
n
Lam LM
Lm
g
LG
PLa PLI
PLg
01-12SierraLeone.indd 7 9/8/06 10:23:34
8 Mining Journal special publication
Organised mining in Sierra Leone really only began after the promulgation of the Minerals Act in 1927. This Act was amended as the Revised Minerals Act in 1960, and was adhered to until 1994, when a more dynamic and investor-friendly Mines and Minerals Decree was passed, which later became the Mines and Minerals Act of 1996. The Law Reform Commission is currently draft-ing a consolidated Mines and Minerals Act, encompass-ing an updated version of the Mines and Minerals Act 1996 and all new legislation into one document. This work is to be completed by the end of 2007.
In the 1930s and 1940s some signi� cant mineral discoveries were recorded by the Geological Survey of Sierra Leone, notably iron ore at Marampa, chromite near Hangha in the Kambui Hills and alluvial diamonds in Kono. These deposits were developed into medium- to
moderate-sized mines by, respectively, Sierra Leone Development Co (Delco), Sierra Leone Chrome Mines and Sierra Leone Selection Trust (SLST).
Delco exploited the Marampa iron ores from 1930 until 1976, mining lateritic material initially but subsequently mining specular haematite (65% Fe). Almost 90 km of railway were constructed with exports routed through the port of Pepel. Shortly before closure the operation was exporting close to 1.0 Mt/y of iron ore. The Hangha chromite de-posits comprise a number of small impersistent lenses averaging 42% Cr2O3. They were worked for a time by open pit and were believed to continue at depth but underground mining was deemed uneconomic.
SLST began mining diamonds in Kono in the 1930s, and by 1951 cumulative production had exceeded 11 Mct. In 1956, the Alluvial Diamond Mining Scheme (ADMS) was introduced in order to regulate the tremendous rush into diamond mining all over Kono District and part of Kenema and Bo Districts. The ADMS was essentially a scheme for artisanal and small-scale miners, and involved licensing mining plots to Sierra Leoneans and regulating the buying and selling of diamonds, as well as their export by the then sole exporter, Diamond Corp of West Africa (DICORWAF), a subsidiary of De Beers.
SLST’s annual production averaged 750,000 ct/y from the mid-1950s until the mid-1970s and was virtually all alluvial. Combined with ADMS output, Sierra Leone’s total diamond output during this period was 1.0-2.0 Mct/y of good-quality diamonds. In 1970,
the government acquired a 51% interest in SLST’s assets through the newly formed National Diamond Mining Co. After 1975, exports declined to less than 0.3 Mct/y by the early 1980s, and o� cial exports dwindled to less than 10,000 ct during the war years (1991-2002).
Gold was discovered in several localities in the years from 1926, in the Sula Mountains and Kangari Hills, and in the Koinadougu, Tonkolili and Bo Districts. The gold is associated with greenstone belts and a number of com-panies conducted small al-luvial operations until 1956. Platinum was � rst recorded in Sierra Leone in 1926 in streams draining the Freetown Peninsula, and some small-scale artisanal operations commenced in 1929.
The Geological Survey discovered bauxite in the Mo-kanji Hills in 1960 and exploration there by Sierra Leone Ore and Metal Co, a subsidiary of Alusuisse, led to the development of a mine in 1963. Bauxite production grew steadily from 150,000 t/y to an annual output of 1.5 Mt in the late 1980s. The production rate subsequently declined to about 800,000 t/y by the time of the mine’s closure in January 1995 when RUF rebel forces overran the operations.
The country’s large rutile deposits located east of the Gbangbama Hills were � rst developed in 1967 by Sherbro Minerals, managed � rst by Pittsburg Plate Glass Co and then Bethlehem Steel Corp. The rutile operation had a di� cult history during the early years but was on a sound footing from 1982 when Nord Resources Corp assumed total ownership through to Consolidated Rutile becoming joint owner in 1993 until the cessation of mining in 1995 for security reasons. The operating company, Sierra Rutile Ltd, was the world’s largest pro-ducer of natural rutile, accounting for about one-quarter of global output.
SIERRA LEONE
AFRICAN DIAMONDS PLC Ireland-based African Diamonds plc is listed on the AIM and Botswana stock ex-changes, and was one of the � rst companies to seek diamond exploration properties in Sierra Leone following the end of the rebel war in January 2002.
The company now holds one exploration licence (ExPL8/02) and two exclusive prospecting licences (EPL.10/02 and 11/02; all dated December 2002), with a total area of over 400 km2, plus one mining licence (ML.1/04, dated March 2004). All of these properties lie within the diamond-rich Kono District in eastern Sierra Leone.
Limited bulk sampling of Pipe 3 under the exploration licence commenced in July 2004 and was completed last September, with the recovery of 1,124 ct, valued at US$198/ct. The largest diamond, weighing 7.2 ct, was valued at US$16,900. Under-ground mining techniques are currently being evaluated.
African Diamonds is also investigating a kimberlite dyke system that extends for over 14,800 m, with an average width of 50 cm at, or near, surface. Geological sampling has shown that the dyke is diamondiferous and that some sections may be high grade. The company is therefore seeking to expand EXPL.8/02 to include the dyke system that is currently identi� ed within EPL.10/02.
Meanwhile, gold has been recovered from streambed samples in EPL.11/02, with a presence ranging from 0.6 ppm to 73 ppm. The so-called Plant 11 was at one time the largest alluvial mining operation in the world, and was in operation for some 25 years. The company’s mining licence covers the undersize tailings from this operation, amounting to around 7 Mt. Initial sampling has shown the presence of both gold and platinum group metals (0.24 to 0.57 g/t Au, and 0.01 g/t PGMs), and artisanal operations have previously demonstrated the presence of small diamonds.
African Diamonds also has major operations in Botswana, where it is a joint venture partner with De Beers. In October 2005, Firestone Diamonds plc issued £2.8 million in new shares to acquire a 6.5% interest in the company.
KOIDU HOLDINGS LTDDiamond producer Koidu Holdings Ltd was incorporated in September 2003 by sharehold-ers BSG Resources Ltd (25%), Magma Diamond Resources Ltd (35%) and Energem Resources Inc (40%). The company’s operations were previously conducted through Branch Energy (renamed Ener-gem Mining).
The company’s assets include the Koidu mining operation in Kono District and four exploration licences (Tongo Field, Matemu, Upper Sewa River and Middle Sewa River).
Chief executive Jan Joubert commented recently: “Koidu Holdings will be the � rst company in the world to implement vertical-pit mining on a kim-berlite orebody.” As part of this strategy, production from the Koidu No1 kimberlite pipe resumed in February 2005. Initial access was provided by tem-porary ramps while construction and commission-ing of a hoisting system was completed. The � rst kibble-load of ore was hoisted in November 2005. Production from the No2 pipe was suspended in May 2005, pending re-evaluation of the economic viability of the orebody.
At the end of December 2005, a total of 176,765 t of kimberlite from No1 pipe had been treated at an average grade of 0.53 ct/t, and a total of 64,218 t were treated from No2 pipe at 0.19 ct/t. A total of 20,466 t of kimberlite from Dyke Zones A and B was treated, at a grade of 0.27 ct/t. Waste material amounted to some 1.3 Mt.
Twelve diamond sales were concluded during 2005. The average price for the parcels from No1 pipe was US$236/ct, while that of No2 pipe was US$207/ct. Diamonds recovered from the grease table were valued separately, and are generally poor quality industrial and coated diamonds, averaging just US$1.15/ct.
Bulk sampling at the company’s Tongo Field project commenced in October 2005, and camp and access routes are being refurbished. Samples from the Lando and Kundu dyke zones are sched-uled for 2006, with drilling of the latter commencing in April 2006.
Developments in 2006 will include the construc-tion of extra capacity at the DMS plant, and a second phase of geological drilling to delineate the ore body at depth. Geohydrological investigations are in progress, with the drilling of eight vertical wells underway in May. Construction of a further 36 resettlement houses has been completed at Koidu.
Continued from page 5
GEO RESOURCES (SL) LTDFreetown-based Geo Resources (SL) Ltd is a geology and mining consultancy that was established in May 1993. The company provides a range of services to explora-tion and mining companies, with a particular emphasis on surveying.
Geo Resources also recently decided to commence exploration in its own right. As a � rst step, the company has taken a prospecting licence for industrial minerals. The EPL ground is known to host mica pegmatites, cassiterite, columbite and wolframite.
Diamond mining along a river in Kono
Phot
o: Pe
ter A
nder
sen
01-12SierraLeone.indd 8 9/8/06 10:23:50
Mining Journal special publication 9
SIERRA LEONE
Formed in January 2004, Njahili Resources plc has assembled a portfolio of exploration properties in Sierra Leone, and is preparing for a listing on London’s AIM market.
The company was founded by three Sierra Leoneans (Farouq Adams, Joe Demby and the now deceased Alex Magona) and two British citizens (Mathew Idiens and Phillippa Je� cock). Njahili is focussed on gold and diamond exploration to provide the early cash � ow to support longer-term e� orts on iron ore, columbite-tantalite, rutile and molybdenite.
Njahili will use the proceeds from its AIM listing to advance the work on six projects; the diamond targets of Gendema and No12 Tailings, and the gold targets of Chetham, Bently, Wara Wara and Bumbuna.
The Gendema alluvial diamond project, in Bo District, is already at the bulk-sampling stage, and previous work on National Diamond Mining Co’s No12 tailings dump at Bumpe near Yengema has established the potential for gold and small diamond recovery.
With regard to the gold projects, Njahili notes that the Chetham target is adjacent to Clu� Gold’s Baomahun project and already has a reported resource containing over 200,000 oz. The company “anticipates rapidly upgrading to an exploration licence and performing work towards de� ning a resource”.
Other projects include the Bagla Hill iron ore target in Kenema District (a 384 Mt deposit in which Bethlehem Steel Co completed a prefeasibility study in the 1970s) and the Little Scarcies rutile deposit.
NJAHILI RESOURCES
DIAMONDSSIERRA Leone is renowned for the quality of its dia-monds and for the recovery of some spectacularly large stones of very high value. The largest ever, discovered in February 1972, was the 969.8 ct ‘Star of Sierra Leone’. More recently, in 1996, two stones weighing 188 ct and 283 ct, plus a 500 ct boart, were recovered and sold.
Peak annual output of around 2 Mct was achieved in the late 1960s, output declining thereafter. By 1997, output was seriously disrupted by RUF rebel activity, most of the diamondiferous areas being overrun.
Sierra Leone’s established diamond � elds cover an area of almost 20,000 km2 (about one-quarter of the country) in the southeastern and eastern parts of Sierra Leone. They are concentrated in Kono, Kenema and Bo Districts, and are mainly situated in the drainage areas of the Sewa, Ba� , Woa, Mano and Moa Rivers. Alluvial diamond concentrations occur in river-channel gravels, � ood-plain gravels, terrace gravels and in gravel residues in soils and swamps. The introduction of the ADMS in 1956 gave rise to a proliferation of artisanal mining activ-ity but large areas of gravel still remain intact because they have a thick overburden cover and are too deeply buried for manual operations.
Kimberlites, the primary source of diamonds, were � rst discovered in 1948 in the Koidu area and subse-quently at Tongo. At Koidu, reserves are estimated by Branch Energy Ltd at 6.3 Mct down to a depth of 600m.
At Tongo, Rex Mining estimates 3.2 Mct to a depth of 600M. A licence has been granted to exploit the known deposits at Koidu and a prospecting licence at Tongo. In addition, Mano River Resources is investigating the ex-tension of the Kimberlite dyke system west of Koidu, and Olympus Development Co is exploring the Panguma kimberlite dykes, part of the Tongo Kimberlite dyke system. (Olympus also has two alluvial licences on the Moa and Moro rivers.) The search for other kimberlitic source rocks continues because it is widely believed that not all alluvial diamond occurrences in Sierra Leone originate from the known kimberlites at Koidu and Tongo.
Within the past three years there have been per-sistent reports of diamond occurrences and artisanal mining in northwestern Sierra Leone. The SLDC has now conducted brief reconnaissance surveys of the areas in question – the Kamaranka-Kamkwei and the Kambia zones. The former is underlain by areas of basement granite and gneiss, and the latter by Kasila gneisses, plus some basement granite. If the mineralogical studies of the heavy mineral samples demonstrate the existence of kimberlite indicator minerals it will be logical to conduct a search for kimberlites. It is suspected that those diamonds that have been found are derived from numerous small and narrow kimberlite dykes which are susceptible to weathering but whose weathering products are di� cult to detect.
Resource potentialGold, platinum and diamonds, rutile and bauxite – Sierra Leone has some of the world’s most valuable resources
A selection of uncut diamonds
Phot
o: V
isual
Med
ia
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10 Mining Journal special publication
RUTILESierra Leone possesses one of the largest natural rutile reserves in the world and until the closure of Sierra Rutile’s operation early in 1995 it was the world’s largest producer of natural rutile. The titanium dioxide mineral was � rst discovered in 1954 in the gravels of the Lanti River south of the Gbangbama region in the Southern Province. Four groups of deposits are known: the Gbang-bama group, the Sembehun group, the Rotifunk deposit and the Kambia deposit. Also, substantial quan-tities of rutile occur in the gravels of the Little Scarcies River, around the con� uence with the Mabole River in Kambia District, and as an accessory mineral in the high-grade gneisses of the Kasila Group.
The Gbangbama group consists of at least six major mineral sands deposits: Mogbwemo, Bamba-Belebu, Pujubu, Lanti, Gbeni and Gangama. The � rst three deposits of the Gbangbama group have now been almost completely mined out. Mining has also taken up about 30% of the Lanti deposit but the remainder are in various stages of mine feasibility studies and could be classi� ed as mineable. At the end of 1994, the Gbang-bama group’s reserves amounted to an estimated (150 Mt of rutile averaging 1.5% to 2% TiO2). There are also large reserves of ilmenite and zircon.
GOLDGold was � rst discovered in northern Sierra Leone in 1926 in the Makoke River near Masumbiri. Further prospecting between 1928 and 1930 proved the existence of extensive alluvial gold� elds in the Sula Mountains/Kangari Hills in the north and central parts of the country.
All greenstone belts in Sierra Leone (with the possible exception of the Marampa Group) are known to
contain gold. Rivers and streams draining these areas also carry gold. Prospecting activities by the Geological Survey established the existence of gold in the following localities within the granite-green-stone terrain of Sierra Leone:
The Sula Mountains area including Lake Sonfon, Maranda and Yirisen.The Kangari Hills area especially Baomahun, Makong and Makele.The Nimini Hills.The Loko Group Schist belt in the Kamakwie-Lami-naia area, Northern Sierra Leone.The Gori Hills.
Lode gold deposits occur in the Lake Sofon area, at Kalmaro, Makong, Baomahun and Komahun. Other gold-bearing areas within the granite-greenstone terrain include the Kangi Hills and the Kambui Hills. The Lake Sonfon area contains steeply-dipping quartz and pegmatite veins show-ing sulphide mineralisation and gold, with assay values of up to 32 g/t.
Mano River Resources and Golden Prospect are undertaking prospect evaluation in this area. Gossanous � oat assaying up to about 90 g/t were also found. At Kalmaro, mineralised quartz veins and lenses intruding talc-chlorite-carbonate schists have been traced for about 800 m along strike assaying up to 27 g/t.
In the Makong area, quartz veins, veinlets and stringers, sometimes with visible gold, occur in the upper reaches of the Kwifwifwi stream. Further exploration in the Makong area has revealed an extensive system of mineralised quartz veins ar-ranged en echelon.
At Baomahun, the gold mineralisation is also associated with sulphides and follows the contact between magnetite-rich garnet-cummingtonite schists and cordierite schists. The contact zone is about 100 m wide and extends for about 1,500 m.
The Baomahun deposit, mined in the 1950s by Maroc Mining, has been the subject of several studies, with Harry Winston Inc installing a pilot heap-leach pad in 1990 and driving an adit into the hillside. The deposit was divided into three areas by the Geological Survey in the 1960s, namely Eastern, Central and Western with an estimated reserve of about 1-2 Moz of gold. This deposit is now being explored by Clu� Gold.
At Komahun in the Nimini Hills, signi� cant gold min-eralisation occurs over an area of about 400 m x 100 m. Drill core assay values of up to 34 g/t and averaging about 8.6 g/t over 20 m have been obtained. Geological Survey studies have delineated signi� cant geochemical anomalies, and Mano River Resources and Afcan Mining are about to start exploration in the area.
BAUXITEThe occurrence of bauxite in Sierra Leone was � rst recorded in 1920 and 1921 on the road from Falaba to Waia in northern Sierra Leone. Other bauxite occurrences include those between Moyamba and
Titanium Resources Group Ltd (TRG) is one of the country’s largest employers and produces three commodities: rutile, ilmenite and bauxite. TRG operates two mines, the Sierra Rutile mine (through Titanium Fields Resources Ltd and Sierra Rutile Ltd) and the SML bauxite mine (through Global Aluminium Ltd and Sierra Mineral Holdings 1 Ltd).
Until operations were suspended in 1995, the two mines accounted for over 75% of the exports of Sierra Leone. The mines restarted production in the � rst quarter of 2006, six months after the company listed and less than three months after the withdrawal of UN peacekeepers.
Sierra Rutile Ltd (SRL) previously accounted for around 30% of the world’s annual supply of natural rutile, a high titanium-bearing feedstock employed in the manufacture of titanium dioxide (TiO2). Ilmenite, a lower titanium-bearing feedstock, is also produced at the mine, which is located in the southwest of Sierra Leone near the Imperri Hills, some 30 km from the Atlantic Ocean, on low-lying coastal plains about 135 km southeast of Freetown.
SRL holds mining leases over a land area of 580 km2, and 19 separate rutile deposits have been identi� ed on these leases, with the majority of these deposits located around the Gbangbama Hills and the remaining deposits existing along the Moyamba Hills. The mining concession is one of the largest natural rutile deposits known in the world, with proved and probable reserves of some 259 Mt at 1.5% recoverable rutile, giving a projected mine life of 19 years.
The mine made its � rst shipment of 7,000 t of rutile in May, and has o� take agreements in place for more than 80% of its expected annual production of 100,000 t of high-grade natural rutile. Construction of a second dredge is under-way, and the company has acquired the Rotifunk deposit, which it is currently assessing. The SML mine made its � rst shipments of bauxite in February, and has now made nine shipments. TRG has long-term o� take agreements with Glencore AG and Alcoa World Alumina LLC for its entire annual production of 1.2 Mt.
The SML mining lease covers an area of 322 km2 and is located approximately 150 km southeast of Freetown. The washing plant is located in Gondama, with other facilities at the Nitti port and, to a lesser extent, in Mokanji. The principal deposits are in Gbonge, Gondama, Jenega, Konta and Wunde.
Proved and probable washed bauxite reserves in the SML lease area are esti-mated at 12.4 Mt grading 53% alumina, with an average silica content of 3%. This reserve estimate will support production for approximately ten years.
TITANIUM RESOURCES GROUPBasama Diamonds Ltd is a joint venture between Petra Diamonds and Mano River Resources. The partners are involved in the Kono kimberlite project, which has several identi� ed � ssures, from which small scale production is envisaged during the next 12 months. Petra has earned a 51% interest in the project by spending US3 million (and is project manager).
The Kono project area is located in the Koidu diamond � eld in the Kono District, 340 km east of Freetown. Petra personnel have opened up the � ssures to a depth of 10 m, and taken samples. A 200 kg sample of kimberlitic material (taken from the Lion 5 � ssure) returned a gem-quality 0.22 ct diamond and three smaller diamonds.
Initial indications suggest that the strike length of the Kono kimberlite � ssures may exceed the total strike length of Petra’s South African � ssure mines. The company believes that the Kono project has the potential to yield grades of ap-proximately 100 ct/100 t, as indicated by Mano River’s original sampling of Lion 5. This returned an average grade of 94 ct/100 t.
Two access points have been selected, one on Lion 5 called lost Shaft and one on Lion 3 called Black Rock Shaft. These sites have been prepared, and shaft sinking is in progress. It is expected that each shaft will be sunk to a depth of 60 m, when adits will be driven along strike of the kimberlite � ssures to recover about 10,000 t of kimberlite from each shaft site.
These kimberlite bulk samples will be processed in separate batches so that grade and diamond values for each kimberlite � ssure can be established to priori-tise mining of the � ssures.
BASAMA DIAMONDS LTD
SIERRA LEONE
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Artisanal Miners in Tongo Field, Sierra Leone
Phot
o: M
ark W
hite
, DFID
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Mining Journal special publicationMining Journal special publication 11
Mano (weathered dolerite sills of the Rokel River Group); the bauxite deposits of the Freetown Peninsula; the Krim-Kpaka deposits in Pujehun District, southern Sierra Leone; and the Kamakwie and Makumre bauxite deposits in northern Sierra Leone. The most important bauxite � nds were made by the Geological Survey in the Mokanji and Gbonge Hills in 1960 and by Sierra Ore and Metal Co (Sieromco) in Port Loko in 1972.
Sierra Leone bauxite ore was formed from Sierra Leone bauxite ore was formed from weathering of the hypersthene/feldspar-rich rocks of the Kasila Group under tropical conditions which resulted in the loss of iron and silica leaving a high concentration of alumina. The Kasila Group forms a high-grade metamorphic belt trending NNW, and is the coastal rim to the West African Craton. Bauxite seems to occur along the entire stretch of the belt from Moyamba in the south, through Port Loko to Kambia District in the northwest.
The Gbonge - Mokanji bauxite belt in the Moyamba District, southern Sierra Leone, was mined by Sieromco (a wholly-owned subsidiary of Alusuisse) from 1963 until 1995. The bauxite belt is 55 km wide and strikes
NNW. A second bauxite deposit is located in the Port Loko area, Northern Province. The Port Loko deposit is the northern exten-sion of the Mokanji bauxite belt, having the same Kasila trend.
The Mokanji deposit is vari-able in quality; blending from various faces yields a shipping grade of 55-56% alumina and 3-4% silica. Sieromco was able to attain a maximum annual production of about 1.5 Mt. Transport over short distances to the port at Nitti, situated on one of the numerous outlets of the Sherbro River, was an added advantage.
The Port Loko bauxite deposit is of medium grade with about 48% alumina and approximately 3-3.5% silica. Feasibility studies carried out by Sieromco indi-
cated a mineable deposit with reserves of over 100 Mt of which 77.3 Mt are proven. The deposit is easily acces-sible, located between 60 km and 90 km from Freetown and at an even shorter distance from the port of Pepel. The old iron-ore railway used by Marampa runs right through the deposit, linking it to the port. Up to 2.0 Mt/y of iron-ore concentrate was usually shipped from Pepel. Other positive factors include the presence of a good road and the infrastructure constructed for the iron-ore road and the infrastructure constructed for the iron-ore mining at Marampa.
PLATINUMAlluvial platinum was discovered in the Big Water and Whale Rivers around York on the Freetown Peninsula in the late 1920s. It was found in almost all the streams draining the western part of the Freetown basic igneous complex and was also reported in eastward � owing streams. Good quantities of platinum were found in association with ilmenite, magnetite, some chromite and specks of gold.
Platinum was mined in the Freetown Peninsula between 1929 and 1949. Most of the platinum was
produced by the panning and sluicing of gravels from the Big Water and Guma Water prospects and from the Big Water and Guma Water prospects and by 1949 about 5,255 oz had been produced. Large nuggets of up to 14g were recovered from the slopes in the Big Water prospect. Examination of coarse platinum grains recovered from the Toke River and Ginger Water indicated proximity to the source rocks.
The streams carrying the best platinum values have their sources in, or cut across in their upper reaches, an intrusion of coarse-grained anorthosite and anorthositic gabbro between Good Luck Hill and York Pass. However, no platiniferous rocks have been intersected by drilling, thus presenting an inter-esting exploration target.
Named after the ancient super continent, Gondwana (Investments) SA is a privately-owned investment and mineral exploration company based in Luxembourg.
The company was founded by Jean-Raymond Boulle (also the founder, in 1993, with Robert Friedland, of Diamond Fields Resources Inc) and has a long history in Sierra Leone.
Over the past decade, Gondwana has been one of the most active explora-tion companies in the country, and is currently focusing its attention on two projects: Port Loko and Rainbow.
The Port Loko bauxite project has been explored over the past couple of years by Gondwana’s partner on this project, Moydow Mines Ltd. An inde-pendent feasibility study is due to be completed shortly.
The Rainbow licence area has been positively sampled for kimberlite indicator minerals, and Gondwana mobilised a team of surveyors earlier this year to assess the feasibility of diverting a river to access mineralised gravels. Meanwhile, interpretation of high-resolution satellite imagery of the project area in January is nearing completion, and the company plans to test the alluvial potential of several selected drainage channels before the onset of the rains in July.
GONDWANA (INVESTMENTS) SAScotland-based African Aluminium Ltd is develop-ing a bauxite mine and alumina re� nery in Sierra Leone, and holds exclusive prospecting licences over 1,700 km2 of prospective land (held in the name of Argyll Resources Corp).
African Aluminium has retained the services of two specialist alumina/bauxite consultancy companies (Worley Parsons and SRK) to evaluate the economic viability of the project, which has a proposed capital cost of some US$1.5 billion, and an estimated annual revenue of US$400 million over a life of at least 35 years.
An initial US$15 million is being spent on a pre-feasibility study. In the � rst stage, the company will concentrate on an exploration programme to determine the bauxite reserves. Other issues to be determined include selecting sites for the re� nery and port, and constructing necessary infrastructure, including road and rail links.
The immediate objective is to de� ne the bauxite resources, and conclude the prefeasibility study. This was part of an agreement signed with the government in 2005, which was subsequently strengthened when the government granted African Aluminium the sole, and exclusive, right to develop an alumina re� nery in Sierra Leone.
AFRICAN ALUMINIUM LTD
SIERRA LEONE
Small Scale Mining Operations in Sandor ChiefdomPhoto: Mark White, DFID
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Mining Journal special publication12 Mining Journal special publication
The Ministry of Mineral Resources (MMR) is responsible for formulating the minerals policy of the country. Its two technical sections are:(i) Mines Division (MD);(ii) Geological Survey Division (GSD).
The Mines Division administers the provisions of the Mines and Minerals Act, the Explosives Act and the regulations made under these Acts. These include the issue of all Mineral Rights on the recommendation of the Mineral Advisory Board (MAB), and the administration and supervision of all activities under these rights. A major function of this division is the issue of mining licences to artisanal miners and the regulation of the mining and marketing of precious minerals through the Govern-ment Gold and Diamond O� ce (GGDO) produced under these licences. A scheme for artisanal licences, the Alluvial Diamond Mining Scheme (ADMS) has been in existence since 1956 and has been a major source of employment for unskilled labour and also a major source of revenue for Sierra Leonean.
The Geological Survey Division (GSD) provides advice to the MMR on all geological matters. It also compiles, publishes and disseminates data and information concern-ing the geology and minerals resources of Sierra Leone. The GSD also supervises prospecting and mineral exploration activities in the country.
The geological database includes: 1:1,000,000 scale map of the whole country; 1:250,000 scale geological maps of northern Sierra Leone (two sheets); and 1:50,000 scale geological maps of the Sula Mountains and Kangari Hills (� ve sheets). There are also airborne geophysical maps for a few limited areas, and geochemical maps for the Sula Mountains and Kangari Hills.
In addition, over the past 15 years the GSD has completed a number of modest geochemical and geological surveys in selected areas. More recently, all the unpub-lished map data amassed during the past 40 years has been put on to 1:250,000 scale base maps has now been published.
The Ministry’s administration is under the Permanent Secretary, who reports to the Minister.
Current exploration and mining activitiesWith the coming into force of the New Mineral Resources Development Policy and Minerals Legislation in 1996, an enabling environment was created for prospective investors, and the hitherto long and cumbersome procedure for the issue of mineral rights was streamlined and simpli� ed.rights was streamlined and simpli� ed.
A pilot Cadastre System has been put place in the Kono District. The aim is to have use of the Cadastre System covering the whole country by 2008. The system would allow an open and transparent method of all mineral rights in the country, and will en-sure correct and prompt payment of fees and noti� cation for renewal as and when due.
MINING ADMINISTRATION AND POLICYThe Government Gold and Diamond O� ce (GDDO), which came into existence in 1985 in pursuance of government policy to rationalise the foreign-exchange regime in the country, is now the Gold and Diamond Division (GDD) within the National Revenue Authority (NRA).
The functions of the GDD are:(i) the valuation of gold and diamonds for export;(ii) the collection of export charges, taxes and royalties on behalf of the government.
This division has become extremely important since the UN Security Council Resolu-tion 1306 of July 2000 on con� ict diamonds. It now handles the certi� cation of all diamonds exported legally from Sierra Leone. For administration purposes it now falls under the National Revenue Authority but its technical function is co-ordinated by the Deputy Director of Mines in the Mines Division.
THE GOLD AND DIAMOND DIVISION
Ownershipi) All rights or ownership in, or search for, mining and disposing of minerals in, under or upon any land in Sierra Leone and its continental shelf, are vested in the Republic of Sierra Leone.ii) The provisions of subsection (i) shall have e� ect notwithstanding any right or ownership or otherwise that any person may possess in and to the soil on or under which minerals are found or situated.
Mineral RightsRights for searching for, mining and disposing of minerals may be acquired and held under a mineral right as provided under the Mines and Minerals Act 1996 and a mineral right means:■ A prospecting licence (exclusive and non-exclusive);■ An exploration licence;■ A mining lease; or■ An artisanal mining licence.Conditions under which much of these licences operate are contained on the Conditions under which much of these licences operate are contained on the department’s website: www.mmr-sl.org
Minerals Administration and LicensingThe Mines and Mineral Decree 1994 (now the Mines and Minerals Act 1996) establishes a Minerals Advisory Board that advises the Minister in the discharge of his statutory responsibilities under it and this, in e� ect, limits the wide discretionary powers he had under the old legislation. The Sierra Leone Chamber of Mines is repre-sented on the Board, along with others from the industry and, together, they present an informed voice on behalf of the industry.
OWNERSHIP OF MINERALS AND ACQUISITION OF MINERAL RIGHTS
SIERRA LEONE
Published by:Mining Communications LtdAlbert House, 1 Singer StreetLondon EC2A 4BQTel: +44 (0)20 7216 6060 Fax: +44 (0)20 7216 6050E-mail: [email protected] Website: www.mining-journal.com
Edited in London by Chris Hinde based on material prepared in Freetown by Usman Boie Kamara, Deputy Director of Mines Design and production: Hannah TalmagePrinted by Stephens & George, Merthyr Tyd� l, UK© Mining Communications Ltd 2006
This supplement is sponsored by the companies listed and has been produced on behalf of the Sierra Leone Ministry of Mineral Resources
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