Mauritania is a country in Northwestern Africa, home to 4.3 million people. It is the 11th larg-est country in Africa, with an area of 1,030,000km2. The country is rich in natural resources, particularly minerals. It has extensive deposits of iron ore, which account for almost 50% of its total exports. It also produces copper and gold from one of the largest mines in Africa. In addition, the country holds enormous de-posits of highly pure gypsum, located 50km north of the capital Nouakchott. The occurrence of such gypsum deposits in a marine basin called ‘Sebkha Ndaghmecha’ has been known since the 1960s, but it was not until the 1980s that geological surveys were thoroughly conducted. These studies showed that gypsum occurs over an area approximately 80km long and 50km wide. The ‘sebkha’ can be divided into two main zones: one active and regularly flooded and one fossil and dry that can be easily accessed by road. Gypsum is found on the surface in the form of moving dunes or translucent crystals with a size of 1-15cm. It is also found in huge quantities 20-50cm below the surface as a form of ‘varved’ or banded gypsum. The gypsum varieties differ in their appearance, chemical composition, and the magni-tude of the reserves. The varved gypsum deposits with a purity of 70-96%, depending on the bed depth, have been estimated at 1.7Bnt, whereas the dune gypsum deposits are approxi-mately 50Mt. The highly pure crystalline gypsum selenites (> 95%) cover a large area, where the deposits are estimated to be around 7Mt.1 Table 1 shows chemical composition of differ-ent types of gypsum found in the Sebkha of Ndaghmecha. Industrial exploitation of gypsum quarries started in 1985 by SAMIA, a Mauritanian-Ku-waiti company, equally owned by the national mining conglomerate SNIM and the Industrial Bank of Kuwait (IBK). SAMIA has per-mit rights for gypsum quarries and extracts mainly varved gypsum from open pit quarries. The mecha-nised exploitation is relatively simple. An overburden of 20-50cm is usually removed before accessing the gypsum, which occurs as a thick layer 1-2m deep. The gypsum covers a bed of sand and shells. Once mined, gypsum is transported by a fleet of trucks to SAMIA’s plaster plant in Nouakchott or to local cement factories. For the gypsum to be shipped abroad, it is transported to a storage area near the Port of Nouakchott. In 2017, total gypsum production of the coun-try amounted to around 200,000t, of which about 30,000t (15%) was processed to make plaster of Paris and 170,000Mt (85%) was consumed by the cement industry, both locally and in the West African sub-region. Of this 170,000t, about 25% was consumed by local cement factories, whereas the remaining 75% was exported, mainly to West African countries such as Senegal, Guinea, Ghana, and Mali.
Gypsum is essential in the production of cement, where it acts as a set-controlling agent. For every 1t of cement made, 30-50kg gypsum is needed. There is no suitable alternative at this time and the sector is set to be a large consumer of gypsum for the foresee-able future. In total it consumes 60% of the 250Mt of gypsum produced worldwide every year.2 In Sub-Saharan Africa cement production is growing very rapidly, fuelled by increasing demand as a result of rapid urbanisation and GDP growth. Gypsum demand is increasing in parallel, currently around 3Mt/yr. In 2016, the cement industry in West Africa imported 1.5Mt of gypsum from Spain alone. Nigeria received more than half of this amount by itself.3 Although there are reported gypsum deposits in some West and Central African countries such as Mali, Nigeria and Angola, there are, to date, no com-mercially exploited gypsum mines in the western part of Africa. All gypsum consumed by the cement industry in this region is currently imported, mainly from Spain. To capture a share of this market, SAMIA has developed a marketing strategy and has acquired the necessary equipment. With the opening of new cement factories in neighbouring Mali in 2013, the company started by exporting its gypsum by trucks over a 1500km distance from its quarry to cement factories near Bamako and Kayes. Then, in 2015, it made its first 35,000t gypsum shipment to Senegal. Since then, it has shipped gypsum from the Port of Nouakchott to many other destinations, including Guinea, Ghana, Cameroon, and the Democratic Republic of Congo. In addition to these west and central African countries, the company plans to become a major gypsum supplier for the cement industry in the Atlantic region, a region that includes the western part of sub-Saharan Africa and the eastern parts of South America and the US. This latter region currently imports more than 2Mt/yr of gypsum from Spain.
In the future, part of this 2Mt/yr could easily be supplied from Mauritania. Indeed, Mauritania has many comparative advantages. Firstly, it is geo-graphically much closer to these markets than Spain. Secondly, the nature, quality, and extent of its gyp-sum reserves represent clear advantages. Last but not least, the gypsum quarries are only 50km from a deepwater port in Nouakchott, with a draft of 12m, at which vessels of up to 45,000t can be loaded. Despite, these clear advantages, there are, however, some supply challenges that need to be addressed before the country and the company can reach their full potentials. These include outbound logistics such as inland transportation, storage, handling, and ship-loading. The availability of ships at Nouakchott and freight rates also constitute major challenges.
Mauritania’s annual production of plaster amounts to about 30,000t, from two gypsum processing plants in Nouakchott. These manufactured products are intended mainly for the local market, but part of the production is also exported by truck to neighbouring Senegal and Mali. These countries are like all West African countries in that they are net importers of plaster and other manufactured gypsum products. Mauritania is thus well positioned to become a major supplier of gypsum manufactured products to these West African markets given its geographical location as well as the agreements it has with the Economic Community of West African States (ECOWAS). Another potential market for Mauritanian gyp-sum is in the agricultural sector of West Africa, where gypsum can be a valuable source of both calcium and sulphur for plant nutrition. It can improve crop yield of locally grown cultures such as peanuts and rice. Gypsum can also be used to treat and reclaim soils polluted by salt water spills as is the case of the Sen-egalese river banks in Senegal and Mauritania or by hydrocarbon spills as is the case of the Niger delta in Nigeria.
Mauritania has enormous deposits of highly pure gypsum that are still largely under-exploited. Open pit gypsum quarries have been exploited by SAMIA, a Mauritanian–Kuwaiti company, since the 1980s to produce gypsum and gypsum products, mainly for the local market. However, it was not until recently that this company has carried out successful export operations to the West and Central African countries. Mauritania has the potential to become a major global supplier of gypsum. It has indeed many comparative advantages, including its geographical location on the Atlantic Ocean, the nature, quality, and extent of its gypsum reserves as well as the loca-tion of its gypsum quarries close to a major deepwater port. However, there are some supply challenges that need to be addressed before the country can take full advantages of these market opportunities.
By Global Gypsum Magazine