Mineral review – Phosphorus
Kawu Musa Idris-Idah, 26th June 2026 This series provides brief insights into minerals underpinning the solar industry. Apatite is the primary mineral source of phosphate. It accumulates over millions of years and mixes with other minerals, forming “phosphate rock”. Apatite always contains calcium and phosphate. Occasionally, fluorine, chlorine and hydroxide are found therein. Phosphate rock is extracted from underground mines or open pits, after which it is ground and sent to a processing plant where impurities are removed and apatite content within the rock is increased. The apatite-concentrated rock mixes with sulphuric acid in reactors at temperatures of about 70 – 80°C to produce phosphoric acid (also called wet-processphosphoric acid) and gypsum as the primary by-product. The resulting phosphoric acid is thus in slurry form, still containing impurities (gypsum, calcium, magnesium, iron etc). Battery manufacturing requires extremely pure phosphoric acid, else performance and lifespan are negatively affected. Substantial effort goes into filtering out the impurities. Via vacuum filtration, suspended solids in phosphoric acid are removed. Although, remnant impurities like fluoride compounds still exist after filtration. Steam stripping and silica addition are some of the methods used to remove fluorides from this mixture. More gypsum, clay and silica are removed via clarification. Subsequently, organic solvents like Tributyl phosphate (TBP) or Di-isopropyl ether are then used to selectively extract only phosphoric acid from the mixture. Extraction happens in several stages and after each stage, the purity of phosphoric acid increases. Finally, an extremely pure phosphoric acid is recovered from the solvent and the solvent is recycled. If trace impurities still exist post-extraction, more reagents could be used to remove them. Further treatment occurs via ion exchange polishing and activated carbon treatment. The resulting extremely pure and concentrated phosphoric acid (battery-grade) is mixed with an iron feedstock like iron sulphate or iron oxide in a reactor at a temperature of about 50–90°C, to produce an iron phosphate slurry. Iron phosphate crystals are precipitated out of the slurry and separated. They are washed and dried to form powdery iron phosphate, which also goes through some steps: first, it is homogeneously mixed with lithium carbonate or lithium hydroxide and a carbon source like glucose, sucrose, carbon black etc. that later forms a conductivecarbon coating during calcination. Homogenously mixing in ball mills or high-shear mixers ensures uniform composition in the slurry. The homogenous slurry undergoes wet milling, enabling more uniformity in the distribution of lithium, iron phosphate and carbon within. The slurry is atomized into fine droplets by a spray dryer. Afterwards, it is heated in a calcination furnace to a temperature of about 600-800°C, in the presence of nitrogen for 5-20 hours. Post-calcination, the material is cooled to produce fine black powder. This final version is used as the cathode active material in lithium iron phosphate battery cells. It is integrated with other components like graphite anodes, separators, electrolytes etc. to form batteries. The table below provides the highest-ranking producing countries of phosphate rock, as per USGS. Africa has excellent representation in phosphate discussions. The next step would be to extract more value from the battery value chain. African countries should therefore aspire to rank high in batteries’ production tables. Production (2025) Country Production (thousand metric tons) China 110,000 Morocco 36,000 United States 20,000 Russia 14,000 Jordan 12,000 Egypt 5,500 Brazil 5,000 Tunisia 3,300 South Africa 2,200 Other countries* 770 Reserves Country Reserves (thousand metric tons) Morocco 50,000,000 China 3,400,000 Egypt 2,800,000 Tunisia 2,500,000 Russia 2,400,000 Algeria 2,200,000 Brazil 1,600,000 South Africa 1,500,000 Other countries* 800,000 *Other countries represents sum total of other minor producers / resource owners. It is a metric that enables comparing a country’s levels to minor producers / resource owners.
Mineral review – Aluminum
Kawu Musa Idris-Idah, 18th May 2026 This series provides brief insights into minerals underpinning the solar industry. Aluminum is the second most abundant metallic element in the earth’s crust after silicon. In terms of global usage, only iron is used more widely than aluminum. In the solar industry, aluminum is used to manufacture solar panel frames, mounting structures, cables and inverter casings. It is less conductive and less expensive than copper, but twice as light and therefore preferred in large-scale electrical installations where copper usage would be expensive. Aluminum can be extracted from several minerals: bauxite, cryolite, alunite, garnet, topaz and chrysoberyl. However, bauxite is the most common source. Bauxite is made of silicon dioxide, iron oxides, titanium dioxide and hydrated aluminum oxides. Via the Bayer Process, aluminum is obtained from bauxite. In this process, bauxite is crushed and mixed with concentrated sodium hydroxide under temperatures ranging from 140°C to 240°C and pressures reaching 35 atm. Aluminum-containing compounds form sodium tetrahydroxoaluminate and the impurities (non-aluminum-containing compounds) like iron oxides form solids that resemble red mud. They are filtered out of the sodium tetrahydroxoaluminate solution via filtration. The remnant solution is cooled and seeded with aluminum hydroxide crystals, resulting in the precipitation of aluminum hydroxide. The precipitate is heated to high temperatures of about 1100 – 1200°C, forming aluminum oxide (alumina). Via electrolysis, aluminum is obtained from alumina. As seen above, aluminum production is linked to production of alumina and bauxite. The tables below provide the highest-ranking producing countries of each, as per USGS. The only African country noted is these tables is Guinea. Guinea has the most bauxite reserves in the world, by far. The country also produces some quantity of alumina, albeit very small in comparison to the likes of China. No African country features in the high ranking producers of the most valuable product in this value chain, aluminum. Bauxite reserves Country Quantity (thousand metric dry tons) Guinea 7,400,000 Other countries* 5,300,000 Australia 3,700,000 Vietnam 3,100,000 Indonesia 2,900,000 Jamaica 2,000,000 China 710,000 Russia 650,000 Alumina production (2025) Country Quantity (thousand metric dry tons) China 93,000 Australia 17,000 Brazil 11,000 India 8,200 Russia 2,900 UAE 2,300 Ireland 1,700 Kazakhstan 1,500 Other countries* 1,300 Guinea 360 Aluminum production (2025) Country Quantity (thousand metric tons) China 45,000 Other countries* 7,000 India 4,200 Russia 3,900 Canada 3,300 UAE 2,700 Bahrain 1,600 Australia 1,500 *Other countries represents sum total of other minor producers / resource owners. It is a metric that enables comparing a country’s levels to minor producers / resource owners.
Mineral review – Silver
Kawu Musa Idris-Idah, 13th April 2026 This series provides brief insights into minerals underpinning the solar industry. Conductors are critical to electricity generation. Silver is the best metallic conductor, but costs more than copper. Copper is also more abundant than silver. Albeit these factors, doses of silver are nonetheless used in panels (busbars) and inverters (switches, relays, circuit breakers, diodes). Silver is obtained directly from argentite or as a by-product of mining metals like copper, lead, zinc and gold. The metallic ore is extracted from the sub-surface and crushed to release the silver-containing bits. Via chemicals and air bubbles, valuable minerals (including silver) are removed as concentrate. Subsequently, concentrate is heated at high temperatures and metals separated from the concentrate, at their appropriate separation temperatures. Post-extraction, refining is required to obtain pure silver. The most common ore from which silver is produced, is lead. Molten zinc is added to lead ore, silver then sticks to zinc and forms a layer that could be removed from the mixture. Electrorefining is the last step where electricity is used to achieve pure silver (exceeding 99.9%). Morocco (179 / 266 tons), Eritrea (53 / 83 tons), South Africa (44 tons) and Botswana (35 / 95 tons) are the top producers of silver in Africa. The two figures provided are from primary and secondary sources. The convention: primary / secondary. The difference noted between both sources results from the complexity in tracking silver produced as a by-product. Nevertheless, the key message is that African countries don’t rank amongst the top ten producers of silver. The table below provides the highest-ranking silver producers, as per USGS 2026. Country Quantity (metric tons) Mexico 6,300 Peru 3,600 China 3,400 Bolivia 1,500 Chile 1,400 United States 1,100 Australia 1,000 Argentina 800 India 800 Kazakhstan 630
Mineral review – Silicon
Kawu Musa Idris-Idah, 9th April 2026 This series provides brief insights into minerals underpinning the solar industry. Silica, also called Silicon (iv) oxide, is obtained from mined quartz sand. Silica is processed further into ferrosilicon or silicon metal. Ferrosilicon is silicon mixed with iron, whilst silicon metal is high purity silicon. Ferrosilicon is used to produce steel, whilst high purity silicon (98%+ pure) is processed further to have much lesser impurities (99.999%+ pure), which could then be used for manufacturing solar panels. South Africa is the only African country that appears in the top 15 silicon producing nations. The country averaged about 10,000 metric tons of silicon metal and 35,000 metric tons of ferrosilicon in 2025. The table below provides the highest-ranking silicon producers, as per USGS 2025. Ferrosilicon Country Quantity (thousand metric tons) China 3500 Russia 420 Brazil 170 Norway 150 Malaysia 120 Bhutan 98 Silicon metal Country Quantity (thousand metric tons) China 4000 Brazil 180 Norway 130 France 68 Australia 47