Sierra Leone's economy is built on the back of its enormous mineral resources, being one of the world's largest natural rutile producers. Mining plays a very crucial and strategic role in Sierra Leone's economic growth and development. It underpinned much of the country's formal economic activity, contributing about 20% of GDP (2012-2014), as much as 15% of fiscal revenues, and accounting for over 90% of exports (2012-2014). Sierra Leone's mines and minerals sector relies mainly on four commodities: diamonds, iron ore, rutile and bauxite. Other commodities produced include zircon, ilmenite, and gold.

The country's mineral exports (circa USD 400 million) accounted for about 62% of total exports in 2019. For large-scale mining operations, rutile and diamond remain the most significant export earnings sources, valued at circa USD 149 million and USD105 million in 2019, respectively. As of 2020, Sierra Leone has 13 large-scale mineral right holders, of which only three are in production: Koidu Limited; Sierra Rutile Limited/Iluka Resources; and Sierra Mineral Holdings 1 Limited (SMHL). Furthermore, upcoming large-scale mining projects include Tongo-Tonguma Kimberlite Project; Sierramin Bauxite Limited; Algom Resources Limited; Wongor Investment and Mining Corporation Limited; Kingho Mining Company Limited; Cheng Li Trading Mining Company; and Meya Mining Limited. Currently, large-scale mining employs less than 2% of the economically active population. In contrast, artisanal and smallscale mining (ASM), including quarrying, provide a livelihood for over 250,000 people and employ about 14% of the total direct and indirect labour force.

Sierra Leone is well-endowed with mineral resources, including iron ore, rutile, diamonds, bauxite, gold, platinum, zircon, ilmenite, chromite and columbite-tantalite (coltan). Extensive alluvial and kimberlitic diamond deposits, bauxite, rutile, and gold, have been found in the east and south of the country. In 2019, the GoSL successfully conducted a systematic programme of extensive and high-resolution, lowaltitude airborne geophysical (aeromagnetic and gamma-spectrometry or radiometric) surveys of the entire country to locate potential new mineral deposits and provide a wealth of geophysical data and information that will illuminate geological thinking for decades to come. The study data is now available at the NMA Office. It will form a vital component of the country's strategy to encourage investment in the mines and minerals sector; help interested investors to further customize interpretation and undertake ground-truthing where necessary; help to position the country as an exciting destination for investors; and provide the opportunity to manage and process reliable geoscientific data in the mining sector- (NMA Strategic Plan 2020-2025).

The Government of Sierra Leone set up the National Minerals Agency under the Ministry of Mines and Mineral Resources in 2012 with a mandate to implement clear policies and regulations, enhance transparency and accountability and ensure mineral resources support economic and social development. Sierra Leone became a member of the Kimberley Process in 2003 to protect the legitimate trade in rough diamonds, and in 2007 enacted the Diamond Cutting and Polishing Act to issue licenses entitling the holder to buy, deal in, export, import as well as cut, polish, crush and set diamonds for the purposes of trade.

The Government has signed up to the Extractive Industries Transparency Initiative (EITI) to further commit to international best practices and to ensure prudent management of extractive sector.

The Government of Sierra Leone remains passionate to fix the underlying challenges associated with the sector. Its aspirations is well documented in the Medium-National Term Development Plan - Under Policy Cluster 2 – Diversifying the economy and promoting growth, Sub-Cluster 2.6 (Improving the management of mineral resources), the GoSL’s objective is to improve the governance and management of the mining sector, including value addition for employment, poverty reduction, community benefit, environmental rehabilitation, and revenue generation.

The Sierra Leone Selection Trust (SLST) began mining diamonds in Kono in 1930 and by 1951 cumulative production annual production averaged 750,000. In 1970, the government acquired a 51% interest and after 1975, exports declined to less than 0.3 Mct/yr and official exports dwindled to less than 10,000 ct during the civil war years (1991 to 2002). The reserves are estimated at 6.3 million carats at Koiduand and 3.2 million carats at Tongo both to a depth of 600m. Fig 3 The Geological Map of Sierra Leone and its associated stratigraphy (Based on Dixey, F, 1925) Abu Bakarr Jalloh et al. / Procedia Earth and Planetary Science 6 (2013) 131 – 138 135 Mining leases were granted to Rex mining Company and Branch Energy to exploit the kimberlite deposits. Branch Energy has transferred its lease to Koidu Holdings S.A. which is currently producing 120,000 carats per year and they have plans to increase production because they have identified reserves to permit ongoing mining for at least another 15 years. They have finished exploring the Tongo dykes and they are now developing it into another producing mine. The search for other kimberlitic source rocks continues because not all alluvial diamond occurrences in the country could be linked with the known sources through alluvial dispersion.

Gold was first discovered in the northern part of the country in 1926 and the prospecting activities by the country’s Geological Survey concluded the existence of gold in many other localities within the granite-greenstone terrain. Following the discovery of gold, several mining companies were involved in alluvial gold production. There was continuous but low mining from 1930 but mining activities stopped in 1956 due to the advent of the Alluvial Mining Scheme. However, mining resumed later, with production increasing in response to favourable market conditions reaching a peak annual production of 30,000 ounces in 1984. Exploration activities resumed in 2003, after the civil conflict and over 20 prospecting licenses were issued by the government. In 2008, Cluff Gold Limited submitted proposals for a mining lease in Baomahun. Recent results from Baomahun have already identified a mineral resource of over 1.1 million ounces of gold and a scoping study confirmed that an open pit mine could produce between 140,000 to 200,000 ounces annually. Another company, Mano River Resources has three gold exploration concessions, which coincides with the richest areas for artisanal gold in the country. All three deposits are considered to have potential gold deposits that are significantly larger than the deposits at Baomahun and Komahun which are the largest currently.

Iron Ore was discovered in the Marampa area in 1926. In 1933, Sierra Leone Development Company (DELCO) started producing iron from Marampa until 1975, when it went into liquidation. In 2005, the London Mining Company (LMC) took over the Marampa concession and has developed it to a mining project. The tailings left by DELCO was reported at 45 million tons from 40 million at an average grade of 27.7% Fe and the primary ore was reported at 1 billion from 92 million at an average grade of 37.7% Fe. LMC started producing tailings and weathered ore to a consistent high quality in November 2011, and has produced as of May 2012, 300,000 dry metric tons of ore and shipped about 230,000 to Europe and China. This result has put the company in position to achieve their 2012 production target of 1.5Mt. The other deposits investigated were the Tonkolili and Bagla Hill deposits. The Tonkolili iron deposit occurs in the Archaean Sula Mountain-Kangari Hills greenstone belt, close to Ferengbeya in the northern part of the country. The iron occurs as residual or secondary ore caps resting on Precambrian banded iron formation. The caps are because of tropical weathering and leaching of underlying quartz-magnetite rocks and the iron rich amphibolites. Estimates for the caps and primary ore are at least 720 million tons at an average grade of 56.3% Fe. African Mineral Limited (AML) have done an extensive drilling for resource modeling and has come up with an estimated reserve of 5 billion tonsat an average grade 56.3% Feand in late 2011 started exporting the cap to china. Annual export figures are not available yet at the Ministry. The Bagla Hill iron ore deposit occurs in the south eastern part of the country and it is a metamorphosed banded magnetite silicate rock made up of alternating layers of magnetite and quartzite. Preliminary evaluation done by Bethlehem Steel Company gave an ore reserve estimate of 384 million tons of primary ore (magnetite) at average grade of 18.1% Fe and about 90 million tons of haematite ore at 34.3% iron. Other minor occurrences are the Krim-Kpaka deposit in the south with 9 million tons at 40% iron and the Kukuna deposit in the north-west which is been currently developed by Cape Lambert Iron Ore Company with15 million tons at 39% iron.

Bauxite occurrence in Sierra Leone was first recorded in 1920 and 1921 at Falaba and Waia respectively, located in the northern part of the country. Other bauxite occurrences included those between Moyamba and Mano which are weathered dolerite sills of the Rockel River Group, the Krim-Kpaka deposits in Pujehun District in the South; the Kamakwie and Makumre bauxite deposits in the North. The most important bauxite deposit finds were made by the Geological Survey in the Mokanji and Gbonge hills in 1960 and by SierraOre and Metal Company (SIEROMCO) in Port Loko in 1972. The Mokanji and Gbonge deposits in Moyamba district were mined by SIEROMCO from 1963 to 1995. The company was able to attain a maximum annual production of about 1.5 million tons. Feasibility studies carried out by SIEROMCO on the Port Loko deposit indicated a mineable deposit with reserves of over 100 million tons out of which 77.3 million tons have been proved. The lease to explore, develop and possibly mine this deposit has been allocated to Gondwana Investments S.A. The former bauxite mine owned by SIEROMCO has now been taken over by a new company; Sierra Minerals Holding and they commenced mining operations in March 2006 and have reported monthly production and export of up to June 2007. In 2006, they produced 1,071,059 mt. and in half a year in 2007, they produced 623,343 mt.

Rutile was discovered in Sierra Leone in 1954 in the gravels of the LantiRiver south of the Gbangbama region in the southern province. Four groups of deposits are known to be distributed around the country: the Gbangbama, Sembehun, Rotifunk and the Kambia deposit. Sierra Leone has the largest natural rutile reserve in the world. The Gbangbama deposit consists of six major deposits: Mogbemo, Bamba-Pelebu, Pujubu, Lanti, Gbeni and Gangama. The first three deposits of the Gbangbama group have been almost completely exhausted. The Lanti deposit is currently being mined. At the end of 1994 the Gbangbama group had an estimated 150 million tons of rutile at grade of 1.5 to 2% and large reserves of ilmenite and zircon. The Sembehun deposit is also made up of six deposits: Kibi, Dodo, Benduma, Komende, Mokamatipa and Matehun. Here exploration results in 1990, revealed the presence of over 180 million tons of rutile with grades ranging from 1.2 to 1.6% rutile. The indicated resource estimate for the Rotifunk deposit in 1990 was 235 million tons at 0.62% rutile. The deposit consists of 6-7m thick horizon of sandy clay within the Bullom Group of sediments. Sierra Rutile Limited (SRL), a subsidiary of Titanium Resources Group (TRG) is now the sole operating company in the country and was the largest producer of natural rutile, accounting for about one quarter of global output before its rutile mine was shut down in 1995.The company began to rehabilitate in 2005 and after a ten-year gap due to the rebel war, began production and exporting in 2006. Rutile production in 2006 and 2007 were as follows: in 2006, 73,803 million tons were produced and in a half year in 2007, 42,005 tons were produced.

In addition to this aforementioned content above, in 2018, GoSL launched a countrywide airborne geophysical survey to provide a wealth of geophysical data and information that will illuminate geological thinking for decades to come. This survey forms a vital component of the NMA’s strategy to encourage investment in the minerals sector was completed in December 2019.

The availability of geophysical data sets helps investors, both local and international to take less risky and hasty decisions on investment in the country. In 2019, the British Geological Survey (BGS) and NMA geologists completed an orientation survey for the proposed countrywide geochemical mapping. NMA geologists, under the guidance of BGS geologists, designed and implemented the Orientation survey campaign in May 2019. The geochemical orientation survey was conducted to:

• primarily form the basis of the development of the Terms of Reference (ToR) for the countrywide geochemical survey contract procurement;
• study the rocks that are typical of Sierra Leone’s geology to determine the most applicable analytical method(s); and
• assess personnel and logistical requirements for the proposed countrywide geochemical mapping campaign.

During the geochemical mapping orientation survey, 57 stream sediments, 63 pan (heavy mineral concentrate) and 34 bulk samples collected from 58 sampling sites across the various lithological units. Sediments and bulk samples were sun-dried at the NMA Laboratory, and all pan concentrates were oven-dried. Sample preparation was undertaken by the BGS and NMA Geologists and Technicians at the NMA Laboratory in June 2019. All samples were dispatched to ALS Laboratories in South Africa in November 2019 for multi-elemental analysis.

Sierra Rutile is a multi-mine operation located in the Bonthe and Moyamba districts. Sierra Rutile has the world’s largest natural rutile deposit and encompasses two operations at Lanti and Gangama; a mineral separation plant; and a dedicated port facility.Sierra Rutile's main product stream is natural rutile and the operation also produces smaller quantities of ilmenite and zircon (in concentrate).Sierra Rutile has an established operating history of more than 50 years and further mine life of at least 20 years, depending on future development options. The Lanti Dry expansion and the Gangama expansion increased the capacity of each mine from 500-600 tonnes per hour of ore to 1,000-1,200 tonnes per hour.

- The Koidu Kimberlite Project is situated in the Kono District of Sierra Leone, approximately 330 km east of the capital city, Freetown. The mining lease area is 4km² and comprises two kimberlite pipes, four dyke zones and a number of blows off the dykes. In 2003, Koidu Holdings set up operations on the property and began dewatering and removing silt from the existing 30m excavation of the No.1 Pipe. While the original planning for the pipes included conventional open pit operations, mitigating factors such as the proximity of the town, the presence of houses close to the perimeter of the pit, the size of the kimberlite pipe and the planned open pit depth, combined with relevant stripping ratios and uncertainties on the grades concerning an underground operation, lent themselves to the vertical pit concept.

- Sierra Mineral Holdings 1 Limited (hereinafter referred to as SMHL) a subsidiary of the Vimetco N.V, a private entity with major operating subsidiaries, Alro SA (88% owned) listed on the Bucharest Stock Exchange and Henan Zhongfu Industry (53.9% owned) listed on the Shanghai Stock Exchange. SMHL is one of the arms of Vimetco Holdings – one of the largest Aluminium producers in the world and has been supplying its parent i.e., Alum its raw materials for a production activity that brings out quality production of Aluminium to supply the global market. Sierra Mineral Holdings 1 Limited holds this mining lease of 321.7 km² that lies along the same belt with the world known Guinea bauxite deposit. In 2019, the production was about 2 million tons of commercial bauxite and the resource base as in 2019 remains at 60 million tons approximately.

- Iron ore is also mined in the Marampa area. The Marampa iron ore deposits have been traced as far as Kukuna near the Guinea border and to the south at Toma and Makalawa. Located in the Port Loko District, in the country’s north, SL Mining is engaged in the exploration, development and production of a high-grade iron ore concentrate with 65% Fe content. The company estimates that Marampa, permitted since 2017, holds about 1 billion tonnes of iron ore with a potential lifespan of 30 years. In 2018 Marampa Mine, in Port Loko District, was transitioning from care and maintenance to be developed into a producing mine by SL Mining Limited.

In February 2019, SL Mining resumed iron ore production at the Marampa Mine following its year-long care & maintenance operation for the most part of 2018. However, the country’s two main operations, Tonkolili Mine (100% owned by China’s Shandong Iron and Steel Group, (SISG) and Marampa Mine (100% owned by SL Mining Ltd), faced numerous regulatory and operational issues, and Sierra Leone’s exports dropped to less than quarter of a million tonne in 2019. SISG and SL Mining mineral rights were cancelled in June 2019 and October 2019 respectively, for failure to comply with their statutory obligations. Dayu Mining, which operates the country’s largest gold mine, has started mining gold concentrate in Masumbiri, Simiria Chiefdom.

ntal analysis.

The main legislation and regulations governing mining activities in Sierra Leone are:

• The Mineral and Mines Act (MMA, 2009 Act): which provides details on how mining is to be conducted in Sierra Leone. It advocates the setting up of a modern cadastral system for issuing, registering and surveying mining operations. The Act provides that all rights of ownership and control of minerals in Sierra Leone including its continental shelf are vested in the State not withstanding any other ownership rights.
• The National Minerals Agency Act, 2012;
• The Extractive Industry Revenue Act 2018;
• The Mines and Minerals Operational Regulations of July 2013;
• The Diamond Cutting and Polishing Act;
• The Diamond Trading Act;
• The Environment Protection (Mines and Minerals) Regulations of July 2013;
• The Income Tax Act, 2000 as amended by the Finance Acts;
• The Customs Act 2011;
• The Sierra Leone Local Content Agency Act, 2016 (No. 3 of 2016);
• The Public Financial Management Act; and
• The Local Content Act.

Mines Minerals Development Act:

The Government of Sierra Leone through its legislative arm has enacted into law the new Mines and Minerals Development Bill. The Act seeks to repeal and replace the Mines and Minerals Act, 2009, to provide for the introduction of new and improved provisions for exploration, mines and minerals development, sale and export for the socio-economic benefit of the people of Sierra Leone, to provide for the facilitation of transparent and accountable management of the minerals sector in accordance with international best practice; to provide for improved employment and employment practices in the mineral sector; to provide for improved welfare of communities affected by exploration, mining and related activities; to provide for more effective measures to reduce the harmful effects of exploration and mining activities on life, property and the environment and to provide for other related matters.

This Act is the product of three mineral sector policies, namely, (i) the Sierra Leone Minerals Policy, (ii) the Artisanal Mining Policy and (iii) the Geo-data Management Policy. Together, these polices create the framework within which the review of the Mines and Minerals Act 2009 occurred. The Act makes provision for Beneficial Ownership Disclosure of natural persons holding 5% or more shares in an extractive company. The Act further makes for mandatory disclosure of Politically Exposed Persons. This further strengthens and demonstrates the GoSL’s commitment to implementing the 2019 EITI Standard.

The Ministry of Mines and Mineral Resources (MMMR) remains the responsible government institution for policy‐making and the minerals sector's management. The NMA is a semi‐autonomous regulator with a clear emphasis on technical strengths and serves as the lead technical entity to implement all Government geological survey, mining cadastre and inspectorate functions.

The NMA, a semi-autonomous agency, was established by the National Minerals Agency Act, 2012, and was officially opened on 7^th March 2013. It is responsible for the day-to-day implementation of the MMDA 2022 and other mining Acts and related regulations, including responsibilities for mineral rights management, collecting and disseminating geological information, regulating the trading of precious minerals, and promoting the rights of communities. The vision statement illustrates NMA's desired future successful state of being, while the mission statement defines NMA's fundamental purpose for its continued existence.

The Environmental Protection Agency (EPA) was established through the Environmental Protection Agency Act (2008). It has the goal of creating and enforcing a strict regulatory framework for environmental regulation in Sierra Leone. It has the mandate to coordinate, monitor and evaluate the implementation of national environmental policies, programmers and projects, including issuing Environmental Impact Assessment (EIA) Licences.

Established in September 2002, by an Act of Parliament, the National Revenue Authority Act, 2002 (Act No-11). The National Revenue Authority in Sierra Leone has the responsibility of assessing and collecting domestic taxes, customs duties and other revenues specified by law, as well as administering and enforcing laws related to these revenues. (nra.gov.sl). For the EITI scoping/reconciliation assignment, the NRA provided data on royalty, mining/ exploration Licences, corporate income tax and diamond exporters’ Licence. 

Local government is provided for by the Local Government Act 2004. The Ministry of Local Government and Rural Development is responsible for local government, which comprises six urban councils (Freetown, Bo, Kenema, Makeni, Koidu and Bonthe) and 16 district councils. In the third sphere of government there are chiefdom councils. The local authorities and chiefdom councils have revenue-raising powers, and they do levy property taxes and Licence fees for mining activities in host communities.

The paramount chiefs and ruling families in the chiefdoms have been recognized and empowered by Sierra Leone’s British Colonial Administration. All chiefdoms have been constituted into a district council. These sub national government agencies receive surface rentals from mining companies.

Parliament provides oversight of the extractive Sector in Sierra Leone and the Members of Parliament that receive 10% surface rent from mining companies are to report on payments received.

The National Minerals Agency is the principal point of contact for the general public in all matters to do with mineral rights, including collection of data on mineral exploration, production and exports. It consists of the Mining Cadastre Office (MCO) and the Geographical Information System (GIS). MCO maintains a mineral rights registry, while GIS keeps the cadastral survey map of Sierra Leone. 

Tender grants exploration and production Licence for oil and gas sector, and the Petroleum Directorate handles all matters relating to licensing, including exploration maps. At present, the Petroleum Directorate does not maintain an electronic oil and gas registry. The National Revenue Authority is the principal government agency responsible for revenue collection from the extractive sector. The collected revenues are transferred to Sierra Leone National Treasury.  The revenues from extractive industries are not separately reported in the national budget. They are recorded primarily as departmental receipts as part of the overall tax revenue estimates for each tax category of the budget books prepared for each year. According to Mines and Minerals Development Act 2022, the state can participate both in mining and oil/gas sectors with a 10% free carried interest.

 Under Article 85 of the Petroleum (Exploration and Production) Act (2011), “Where the state elects to participate in a petroleum licence, it shall have an initial carried interest of at least 10% and may acquire an additional paying interest up to a declared maximum within a specified period of time from the date a discovery is declared to be commercial discovery. Although the National Minerals Agency has disclosed some contracts on its website, the Government of Sierra Leone does not have a policy and law on contract disclosure. The Petroleum Sector is yet to commence such initiatives although agreement made can be viewed by the public on gazette.