History of aluminium
Aluminium or aluminum is a chemical element with symbol Al and atomic number 13. At standard conditions, aluminium forms a bright silvery metal; this metal is unusually light and resistant against corrosion. Chemically, aluminium is a main-group element that normally assumes the +3 oxidation state. Aluminium is the third most abundant element in the Earth's crust; as such, it is widespread in human-related activities. Aluminium is produced in tens of millions of metric tons; the metal is commonly alloyed to improve some characteristics, such as hardness. Aluminium has no biological role but is not particularly toxic.
The aluminium compound alum has been known since the 5th century BCE and was extensively used by the ancients for dyeing and city defense; during the Middle Ages, the former use made alum a subject of international commerce. Scientists of the Renaissance believed alum was a salt of a new earth; during the Age of Enlightenment, it was established that the earth was an oxide of a new metal. Discovery of this metal was announced in 1825 by Danish physicist Hans Christian Ørsted, whose work was extended by German chemist Friedrich Wöhler.
Aluminium was difficult to refine and thus uncommon in actual usage. Soon after its discovery, the price of aluminium exceeded that of gold and was only reduced after the initiation of the first industrial production by French chemist Henri Étienne Sainte-Claire Deville in 1856. Aluminium became much more available to the general public with the Hall–Héroult process independently developed by French engineer Paul Héroult and American engineer Charles Martin Hall in 1886 and the Bayer process developed by Austrian chemist Carl Joseph Bayer in 1889. These processes have been used for aluminium production up to the present.
Introduction of these methods to mass production of aluminium led to the extensive use of the metal in industry and everyday lives. Aluminium has been used in aviation, engineering, construction, and packaging thanks to its lightness and resistance against corrosion. Its production grew exponentially in the 20th century and it became an exchange commodity in the 1970s. In 1900, production was 6,800 metric tons; in 2015, it was 57,500,000 tons.
The history of aluminium was shaped by the usage of its compound alum. The first written record of alum was made in the 5th century BCE by Greek historian Herodotus. The ancients used alum as a dyeing mordant, in medicine, as a fire-resistant coating for wood, and in chemical milling. Aluminium metal was unknown. Roman writer Petronius mentioned in his novel Satiricon that an unusual glass had been presented to the emperor: after it was thrown on the pavement, it did not break but only deformed and it was brought to the former shape with a hammer. After learning from the inventor that nobody else knew how to produce this material, the emperor had the inventor executed so that it does not diminish the price of gold. Variations of this story were briefly mentioned in Natural History by Roman historian Pliny the Elder (who noted the story had "been current through frequent repetition rather than authentic") and Roman History by Roman historian Cassius Dio. Some sources suggest this glass could be aluminium.[a][b] It is possible that aluminium-containing alloys were produced in China during the reign of the first Jin dynasty (265–420).[c]
After the Crusades, alum was a subject of international commerce; it was indispensable in the European fabric industry. Small alum mines were worked in Catholic Europe but most alum came from the Middle East. Alum continued to be traded through the Mediterranean Sea until the mid-15th century, when the Ottomans greatly raised export taxes. In 1460, Giovanni da Castro, godson of the Pope Pius II, discovered a rich source of alum at Tolfa near Rome and reported excitedly to his godfather, "today I bring you victory over the Turk".[d] This newly found alum long played an important role in European pharmacy but the high prices set by the papal government eventually made other states start their own production; large-scale alum mining came to other regions of Europe in the 16th century.
Establishing the nature of alumEdit
At the start of the Renaissance, the nature of alum remained unknown. Around 1530, Swiss physician Paracelsus recognized alum as separate from vitriole (sulfates) and suggested that it was a salt of an earth. In 1595, German doctor and chemist Andreas Libavius demonstrated alum and green and blue vitriole were formed by the same acid but different earths; for the undiscovered earth that formed alum, he proposed the name "alumina". In 1702, German chemist Georg Ernst Stahl stated the unknown base of alum was akin to lime or chalk; this mistaken view was shared by many scientists for half a century. In 1722, German chemist Friedrich Hoffmann suggested the base of alum was a distinct earth. In 1728, French chemist Étienne Geoffroy Saint-Hilaire claimed alum was formed by an unknown earth and sulfuric acid; he mistakenly believed burning of that earth yielded silica. In 1739, French chemist Jean Gello proved the earth in clay and the earth resulting from the reaction of an alkali on alum were identical. In 1746, German chemist Johann Heinrich Pott showed the precipitate obtained from pouring an alkali into a solution of alum was different from lime and chalk.
In 1754, German chemist Andreas Sigismund Marggraf synthesized the earth of alum by boiling clay in sulfuric acid and adding potash. He realized that adding soda, potash, or an alkali to a solution of the new earth in sulfuric acid yielded alum. He described the earth as alkaline, as he had discovered it dissolved in acids when dried. Marggraf also described salts of this earth: the chloride, the nitrate, and the acetate. In 1758, French chemist Pierre Macquer wrote that alumina[e] resembled a metallic earth. In 1767, Swedish chemist Torbern Bergman synthesized alum by boiling alunite in sulfuric acid and adding potash to the solution. He also synthesized alum as a reaction product between sulfates of potassium and earth of alum, demonstrating that alum was a double salt. In 1776, German pharmaceutical chemist Carl Wilhelm Scheele demonstrated that both alum and silica originated from clay and alum did not contain silicon. Geoffroy's mistake was only corrected in 1785 by German chemist and pharmacist Johann Christian Wiegleb who determined the earth of alum could not be synthesized from silica and alkalis, contrary to contemporary belief.
Swedish chemist Jöns Jacob Berzelius suggested in 1815 the formula AlO3 for alumina. The correct formula, Al2O3, was established by German chemist Eilhard Mitscherlich in 1821; this helped Berzelius determine the correct atomic weight of the metal, 27.
Synthesis of metalEdit
In 1760, French chemist Theodor Baron de Henouville suggested alumina was a metallic earth and attempted to reduce it to its metal, but with no success. He claimed he had tried every method of reduction known at the time, though his methods were not published. It is probable that he mixed alum with carbon or some organic substance, with salt or soda for flux, and heated it in a charcoal fire. In 1782, French chemist Antoine Lavoisier wrote he considered alumina was an oxide of a metal with an affinity for oxygen so strong that no known reducing agents could overcome it.
In 1790, Austrian chemists Anton Leopold Ruprecht and Matteo Tondi repeated Baron's experiments, significantly increasing the temperatures. They found small metallic particles they believed were the sought-after metal; but later experiments by other chemists showed these were iron phosphide from impurities in charcoal and bone ash. German chemist Martin Heinrich Klaproth commented in an aftermath, "if there exists an earth which has been put in conditions where its metallic nature should be disclosed, if it had such, an earth exposed to experiments suitable for reducing it, tested in the hottest fires by all sorts of methods, on a large as well as on a small scale, that earth is certainly alumina, yet no one has yet perceived its metallization." Lavoisier in 1794 and French chemist Louis-Bernard Guyton de Morveau in 1795 melted alumina to a white enamel in a charcoal fire fed by pure oxygen but found no metal. American chemist Robert Hare in 1802 melted alumina with an oxyhydrogen blowpipe, also obtaining the enamel, but still found no metal.
In 1807, British chemist Humphry Davy successfully electrolyzed alumina with alkaline batteries, but the resulting alloy contained potassium and sodium, and Davy had no means to separate the desired metal from these. He then heated alumina with potassium, forming potassium oxide, but was unable to produce the sought-after metal. In 1808, Davy set up a different experiment on electrolysis of alumina, establishing that alumina decomposed in the electric arc, but formed metal alloyed with iron and he was unable to separate the two. Finally he tried yet another electrolysis experiment, seeking to collect the metal on iron, but was again unable to separate the coveted metal from it. Davy suggested the metal be named alumium in 1808 and aluminum in 1812, thus producing the modern name. Other scientists used the spelling aluminium; the former spelling regained usage in the United States in the following decades.
In 1824, Danish physicist and chemist Hans Christian Ørsted attempted the production of the metal. He reacted anhydrous aluminium chloride with potassium amalgam, yielding a lump of metal that looked similar to tin. He presented his results and demonstrated a sample of the new metal in 1825. In 1826, he wrote, "aluminium has a metallic luster and somewhat grayish color and breaks down water very slowly"; this suggests that he had obtained an aluminium–potassium alloy rather than pure aluminium. Ørsted gave little importance to his discovery. He did not notify either Davy or Berzelius, both of whom he knew, and published his work in a Danish magazine unknown to the general European public. As a result, he is often not credited as the discoverer of the element; some earlier sources went further and claimed Ørsted had not isolated aluminium.
Berzelius tried to isolate the metal in 1825 by carefully washing the potassium analog of the base salt in cryolite in a crucible. Prior to the experiment, he had correctly identified the formula of this salt as K3AlF6. He found no metal, but his experiment came very close to succeeding and was successfully reproduced many times later. Berzelius's mistake was in using an excess of potassium, which made the solution too alkaline; the alkaline solution dissolved all the newly formed aluminium.
In 1827, German chemist Friedrich Wöhler visited Ørsted and received explicit permission to continue the aluminium research, which Ørsted "did not have time" for. Wöhler repeated Ørsted's experiments but did not identify any aluminium. (Wöhler later wrote to Berzelius, "what Oersted assumed to be a lump of aluminium was certainly nothing but aluminium-containing potassium".) He conducted a similar experiment, mixing anhydrous aluminium chloride with potassium, and produced a powder of aluminium. After hearing about this, Ørsted suggested his own aluminium may have contained potassium. Wöhler continued his research and in 1845 was able to produce small pieces of the metal and described some of its physical properties. Wöhler's description of the properties indicates that he obtained impure aluminium. Other scientists also failed to reproduce Ørsted's experiment, and Wöhler was credited as the discoverer. While Ørsted was not concerned with the priority of the discovery, some Danes tried to demonstrate he had obtained aluminium, and in 1921, the reason for the inconsistency between Ørsted's and Wöhler's experiments was discovered by Danish chemist Johan Fogh, who demonstrated that Ørsted's experiment was successful thanks to use of a large amount of excess aluminium chloride and an amalgam with low potassium content. In 1936, scientists from American aluminium producing company Alcoa successfully recreated that experiment. However, many later sources still referred to Wöhler as the discoverer.
My first thought was I had laid my hands on this intermediate metal which would find its place in man's uses and needs when we would find the way of taking it out of the chemists' laboratory and putting it in the industry.
Since Wöhler's method could not yield large amounts of aluminium, the metal remained uncommon; its cost had exceeded that of gold before a new method was devised. In 1852, aluminium cost US$545 per pound.
French chemist Henri Étienne Sainte-Claire Deville announced an industrial method of aluminium production in 1854 at the Paris Academy of Sciences. Aluminium chloride could be reduced by sodium, a metal more convenient and less expensive than potassium used by Wöhler. Deville was able to produce an ingot of the metal. Napoleon III of France promised Deville an unlimited subsidy for aluminium research; in total, Deville used 20 times the annual income of an ordinary family. Napoleon's interest for aluminium lied in its potential military use: he wished weapons, helmets, armor, and other equipment for the French army could be made of the new light shiny metal. While the metal was still not displayed to the public, Napoleon is reputed to have held a banquet where the most honored guests were given aluminium utensils while others made do with gold.
Twelve small ingots of aluminium were subsequently exhibited for the first time to the general public at the Exposition Universelle of 1855. The metal was presented as "the silver from clay" (aluminium is very similar to silver visually), and this name was soon widely used. It caught wide attention, but not all of it was favorable. Newspapers wrote, "The Parisian expo put an end to the fairy tale of the silver from clay", saying that much of what had been said about the metal was exaggerated if not untrue and that the amount of the presented metal—about a kilogram—contrasted with what had been expected and was "not a lot for a discovery that was said to turn the world upside down". However, the metal was noticed by the avantgarde writers of the time—Charles Dickens, Nikolay Chernyshevsky, and Jules Verne—who envisioned its usage in the future. Overall, the fair led to eventual commercialization of the metal. The price of aluminium fell to US$115 per pound in 1855 and to $17 in 1859. At the next fair in Paris in 1867, the visitors were presented with aluminium wire and foil.
Manufacturers did not wish to devote resources from producing well-known metals, such as iron and bronze, to experiment with a new one; moreover, produced aluminium was still not of great purity and differed in properties by sample. This led to the initial general reluctance to produce the new metal. The world's first industrial production of aluminium was established at a smelter in Rouen in 1856 by Deville and partners. Deville's smelter moved that year to La Glacière and then Nanterre, and in 1857 to Salindres. For the factory in Nanterre, an output of 2 kilograms of aluminium per day was recorded; purity of the produced aluminium was 98%. In 1860, Deville sold his aluminium interests to Henri Merle, a founder of Compagnie d'Alais et de la Camargue; this company will dominate the aluminium market in France decades later. The factory in Salindres used bauxite as the primary aluminium ore; some chemists, including Deville, sought to use cryolite, but with little success. British engineer William Gerhard set up a plant with cryolite as the primary raw material in Battersea, London, in 1856, but technical and financial difficulties forced the closure of the plant in three years. British ironmaster Isaac Lowthian Bell produced aluminium from 1860 to 1874. During the opening of his factory, he waved to the crowd with a unique and costly aluminium top hat. No statistics about this production can be recovered, but it "cannot be very high". Deville's output grew to 1 metric ton per year in 1860; 1.7 tons in 1867; 1.8 tons in 1872. At the time, demand for aluminium was low: for example, sales of Deville's aluminium by his British agents equaled 15 kilograms in 1872. Aluminium at the time was often compared with silver; like silver, it was found to be suitable for making jewelry and objéts d'art.
Other production sites began to appear in the 1880s. British engineer James Fern Webster launched the industrial production of aluminium by reduction with sodium in 1882; his aluminium was much purer than Deville's (it contained 0.8% impurities whereas Deville's typically contained 2%). World production of aluminium in 1884 equaled 3.6 tons. In 1884, American architect William Frishmuth combined production of sodium, alumina, and aluminium into a single technological process; this contrasted with the previous need to collect sodium, which combusts in water and sometimes air. In 1886, American engineer Hamilton Castner devised a method of cheaper production of sodium, which decreased the cost of aluminium to $8 per pound, but he did not have enough capital to construct a large factory like Deville's. In 1887, he constructed a factory in Oldbury; Webster constructed a plant nearby and bought Castner's sodium to employ it in his own production of aluminium. In 1887, Aluminium- und Magnesiumfabrik started production in Hemelingen. In 1889, German metallurgist Curt Netto launched a method of reduction of cryolite with sodium that produced aluminium containing 0.5–1% of impurities. The United States Department of the Interior estimated in 1890 that the total amount of unalloyed aluminium produced from 1860 to 1889 in France, the United Kingdom, the United States, and Germany equaled 116 short tons (105 metric tons), suggesting that "the indications are that the manufacture will be so largely increased from now on that this amount will soon be exceeded from now on by the annual production".
Aluminium was first synthesized electrolytically in 1854 independently by the German chemist Robert Wilhelm Bunsen and Deville. Their electrolysis methods did not become the basis for industrial production of aluminium because electrical supplies were inefficient at the time; this only changed with the invention of the dynamo, which made creation of large amounts of electricity possible, by Belgian engineer Zénobe-Théophile Gramme in 1870 and the three-phase current, which made transmission of this electricity over large distances possible, by Russian engineer Mikhail Dolivo-Dobrovolsky in 1889. Soon after the discovery, Bunsen moved on to other areas of interest while Deville's work was noticed by Napoleon III; this was the reason why Deville's Napoleon-funded research on aluminium production had been started. Deville quickly realized electrolytic production was impractical at the time and moved on to the chemical methods.
The first large-scale production method was independently developed by French engineer Paul Héroult and American engineer Charles Martin Hall in 1886; it is now known as the Hall–Héroult process. Electrolysis of pure alumina is impractical given its very high melting point; both Héroult and Hall realized its melting point could be significantly lowered by presence of molten cryolite. Héroult could not find enough interest in his invention as demand for aluminium was still small and Deville's factory in Salindres did not wish to improve their process. In 1888, Héroult and his companions founded Aluminium Industrie Aktien Gesellschaft and started industrial production of aluminium bronze in Neuhausen am Rheinfall. This production was only active for a year, but during that time, Société électrométallurgique française was founded in Paris. The society purchased Héroult's patents and appointed him as the director of a smelter in Isère, which would produce aluminium bronze on a large scale at first and pure aluminium in a few months.
At the same time, Hall produced aluminium by the same process in his home at Oberlin and successfully tested it at the smelter in Lockport. He then sought to employ it for a large-scale production. The smelter owners did not wish to change their production methods because they feared a mass production of aluminium would immediately drop the price of the metal. The president of the company considered purchasing Hall's patent to ensure that the competitors would not make use of it. Hall founded the Pittsburgh Reduction Company in 1888 and initiated production of aluminium. In the coming years, this technology was improved and new factories were constructed.
The Hall–Héroult process converts alumina into the metal; Austrian chemist Carl Joseph Bayer discovered a way of purifying bauxite to yield alumina in 1889, now known as the Bayer process. Bayer sintered bauxite with alkali and leached it with water; after stirring the solution and introducing a seeding agent to it, he found a precipitate of pure aluminium hydroxide, which decomposed to alumina on heating. In a few years, he discovered that the aluminium contents of bauxite dissolved in the alkaline leftover from isolation of alumina solids; this was crucial for the industrial employment of this method.
By the end of 1889, a consistently high purity of aluminium produced via electrolysis had been achieved. In 1890, Webster's factory went obsolete after an electrolysis factory had been opened in England. Netto's main advantage, high purity of the resulting aluminium, was outmatched by electrolytic aluminium and his company closed next year. Compagnie d'Alais et de la Camargue also decided to switch to electrolytic production, and their first plant using this method was opened in 1895.
Modern production of the aluminium metal is based around the Bayer and Hall–Héroult processes. The Hall–Héroult process was further improved in 1920 by a team led by Swedish chemist Carl Wilhelm Söderberg. Previously, anode cells had been made from pre-baked coal blocks, which quickly corrupted and required replacement; the team introduced continuous electrodes made from a coke and tar paste in a reduction chamber. This greatly increased the world output of aluminium.
Give me 30,000 tonnes of aluminium, and I will win the war.
The prices for aluminium declined, and by the early 1890s, the metal had become widely used in jewelry, eyeglass frames, optical instruments, and many everyday items. Aluminium tableware began to be produced in the late 19th century and gradually supplanted copper and cast iron tableware in the first decades of the 20th century. Aluminium foil was popularized at that time. Aluminium is soft and light, but it was soon discovered that alloying it with other metals could increase its hardness while preserving low density. Aluminium alloys found many uses in the late 19th and early 20th centuries. For instance, aluminium bronze is applied to make flexible bands, sheets, and wire, and is widely employed in the shipbuilding and aviation industries. Aviation used a new aluminium alloy, duralumin, invented in 1903. Aluminium recycling started in the early 1900s and has been used extensively since as aluminium is not impaired by recycling and thus can be recycled repeatedly. At this point, only the metal that had not been used by end-consumers was recycled. During World War I, major governments demanded large shipments of aluminium for light strong airframes. They often subsidized factories and the necessary electrical supply systems. Overall production of aluminium peaked during the war: world production of aluminium in 1900 was 6,800 metric tons; in 1916, annual production exceeded 100,000 tons. The war created a greater demand for aluminium, which the growing primary production was unable to fully satisfy, and recycling grew intensely as well. The peak in production was followed by a decline, then a swift growth.
During the first half of the 20th century, the real price for aluminium continuously fell from $14,000 per metric ton in 1900 to $2,340 in 1948 (in 1998 United States dollars) with some exceptions such as the sharp price rise during World War I. Aluminium was plentiful and in 1919, Germany began to replace its silver coins with aluminium ones; more and more denominations were switched to aluminium coins as hyperinflation progressed in the country. By the mid-20th century, aluminium had become a part of everyday lives, becoming an essential component of houseware. Aluminium freight cars first appeared in 1931. Their lower mass allowed them to carry more cargo. During the 1930s, aluminium emerged as a civil engineering material, being used in both basic construction and building interiors, and advanced its use in military engineering for both airplanes and tank engines.
Aluminium obtained from recycling was considered inferior to primary aluminium because of poorer chemistry control as well as poor removal of dross and slags. Recycling grew overall but largely depended on the output of primary production: for instance, as electric energy prices went down in the United States in the late 1930s, more primary aluminium could be produced in the energy-expensive Hall–Héroult process, rendering recycling less needed, and thus aluminium recycling rates went down. By 1940, mass recycling of post-consumer aluminium had begun.
During World War II, production peaked again, first exceeding 1,000,000 metric tons in 1941. Aluminium was heavily used in aircraft production and thus a strategic material of extreme importance; so much so that when Alcoa (successor of Hall's Pittsburgh Reduction Company and the aluminium production monopolist in the United States at the time) did not expand its production, the United States Secretary of the Interior proclaimed in 1941, "If America loses the war, it can thank the Aluminum Corporation of America". In 1939, Germany was world's leading producer of aluminium; the Germans thus saw aluminium as their edge in the war. Aluminium coins continued to be used but while they symbolized decline on introduction, by 1939, they had come to represent power. (In 1941, they began to be withdrawn from circulation.) After the United Kingdom was attacked in 1940, it started an ambitious program of aluminium recycling; the newly appointed Minister of Aircraft Production appealed to the public to donate any household aluminium for airplane building. The Soviet Union received 328,100 metric tons of aluminium from its co-combatants from 1941 to 1945; this aluminium would be used in aircraft and tank engines. Without these shipments, the output of the Soviet aircraft industry would have fallen by over a half. Production fell after the war but then rose again.
Earth's first artificial satellite, launched in 1957, consisted of two joined aluminium hemispheres, and almost all subsequent spacecraft have been made of aluminium. The aluminium can was first manufactured in 1956 and employed as a container for drinks in 1958. In the 1960s, aluminium was employed for production of wires and cables. Since the 1970s, high-speed trains have commonly used aluminium for its lightness. For the same reason, the aluminium content of cars is growing.
By 1955, the world market had been mostly divided by the Six Majors: Alcoa, Alcan (originated as a part of Alcoa), Reynolds, Kaiser, Pechiney (merger of Compagnie d'Alais et de la Camargue that bought Deville's smelter and Société électrométallurgique française that hired Héroult), and Alusuisse (successor of Héroult's Aluminium Industrie Aktien Gesellschaft); their combined share of the market equaled 86%. From 1945, aluminium consumption grew by almost 10% each year for nearly three decades, gaining ground in building applications, electric cables, basic foils, and the aircraft industry. In the early 1970s, an additional boost came from the development of aluminium beverage cans. The real price declined until the early 1970s; in 1973, the real price equaled $2,130 (in 1998 United States dollars). The main drivers of the decline of prices were the decline of extraction and processing costs over technological progress as well as the growth of aluminium production, which first exceeded 10,000,000 metric tons in 1971.
In the late 1960s, governments became aware of waste from the industrial production; they enforced a series of regulations favoring recycling and waste disposal. Söderberg anodes, which save capital and labor to bake the anodes but are more harmful to the environment (because of a greater difficulty in collecting and disposing of the baking fumes), fell in disfavor, and production began to shift back to the pre-baked anodes. The aluminium industry started to promote recycling of aluminium cans in an attempt to avoid restrictions on them. This sparked recycling of aluminium previously used by end-consumers: for example, in the United States, levels of recycling of such aluminium increased 3.5 times from 1970 to 1980 and 7.5 times to 1990. Production costs for primary aluminium grew in the 1970s and 1980s, and this also contributed to the rise of aluminium recycling.
In the 1970s, the increased demand for aluminium made it an exchange commodity; it entered the London Metal Exchange, world's oldest industrial metal exchange, in 1978. Since then, aluminium has been traded for United States dollars and its price fluctuated along with the exchange rates of the currency. The need to exploit lower-grade poorer quality deposits and the use of fast increasing input costs (above all, energy, but also bauxite) as well as changes in exchange rates and greenhouse gas regulation increased the net cost of aluminium; the real price grew in the 1970s.
The increase of the real price and changes of tariffs and taxes started redistribution of the world producers' shares: the United States, the Soviet Union, and Japan accounted for nearly 60% of world's primary production in 1972 (and their combined share of consumption of primary aluminium was also close to 60%), but their combined share only slightly exceeded 10% in 2012. The production shift started in the 1970s; production started to move from the United States, Japan, and Western Europe to Australia, Canada, the Middle East, Russia, and China, where it was cheaper due to lower electricity prices and favorable regulation from states, such as low taxes or subsidies. Production costs in the 1980s and 1990s declined because of advances in technology, lower energy and alumina prices, and high exchange rates of the United States dollar.
In the 2000s, the BRIC countries' combined share grew from 32.6% to 56.5% in primary production and 21.4% to 47.8% in primary consumption. China has accumulated an especially large share of world production, thanks to abundance of resources, cheap energy, and governmental stimuli; it also increased its share of consumption from 2% in 1972 to 40% in 2010. The only other country with a two-digit percentage was the United States with 11%; no other country exceeded 5%. In the United States, Western Europe, and Japan, most aluminium was consumed in transportation, engineering, construction, and packaging.
In the mid-2000s, increasing energy, alumina, and carbon (used in anodes) prices caused an increase in production costs. This was amplified by a shift in currency exchange rates: not only a weakening of the United States dollar, but also a strengthening of the Chinese yuan. The latter became important as most Chinese aluminium was relatively cheap.
The world output continued to grow: in 2013, annual production of aluminium exceeded 50,000,000 metric tons. In 2015, it was a record 57,500,000 tons. Its real price (in 1998 United States dollars) in 2015 was $1,340 per metric ton ($1,940 per ton in contemporary dollars).
- Deville had established that heating a mixture of sodium chloride, clay, and charcoal yields numerous aluminium globules. This was published in the Proceedings of the Academy of Sciences but eventually forgotten. French chemist André Duboin discovered that heating a mixture of borax, alumina, and smaller quantities of dichromate and silica in a crucible formed impure aluminium. Boric acid is abundant in Italy. According to Duboin, this hints at the possibility that boric acid, potash, and clay under the reducing influence of coal may have produced aluminium in Rome.
- A similar story is attributed to Pliny, which instead mentions a light bright metal extracted from clay—a description that matches that of aluminium. Both Petronius and Pliny, however, mentioned glass (and Dio did not mention the material at all). A possible source of the error is French general Louis Gaspard Gustave Adolphe Yvelin de Béville, who was openly cited by Deville in 1864. De Béville searched in the Roman sources for possible ancient mentions of the new metal and discovered among others the story in Satiricon. De Béville might have misinterpreted Petronius's expression aurum pro luto habere (literally "to have gold as dirt"), assuming that lutum stands for "clay" (a possible translation), whereas the word throughout the book actually means something valueless in general. German chemist Gerhard Eggert concluded that this story was erroneous. After evaluating other possible explanations, he announced the original story was also probably made up; however, he did not evaluate Duboin's suggestion.
- Alumina was plentiful and could be reduced by coke in the presence of copper, giving aluminium–copper alloys. Existing works by the Chinese alchemists show that if anywhere at the time, alloys with a small content of aluminium could be produced in China. The Chinese did not have the technology to produce pure aluminium and the temperatures needed (around 2000 °C) were not achievable. A number of high-aluminium artifacts were found in China relating to the times of the first Jin dynasty but it was later shown the technology needed to make them was not achievable at the time and thus the artifacts were not authentic.
- "Today, I bring you the victory over the Turk. Every year they wring from the Christians more than three hundred thousand ducats for the alum with which we dye wool. For this is not found among the Latins except a very small quantity. [...] But I have found seven mountains so rich in this material that they could supply seven worlds. If you will give orders to engage workmen, build furnaces, and smelt the ore, you will provide all Europe with alum and the Turk will lose all his profits. Instead they will accrue to you..."
- The terms "earth of alum" and "alumina" refer to the same substance. German-speaking authors mentioned in this section used "earth of alum" (Alaun-Erde), while French authors used "alumina" (alumine).
- Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2 ed.). Butterworth-Heinemann. p. 217. ISBN 978-0-08-037941-8.
- Frank, W. B. (2009). "Aluminum". Ullmann's Encyclopedia of Industrial Chemistry. Wiley-VCH. doi:10.1002/14356007.a01_459.pub2. ISBN 978-3527306732.
- Drozdov 2007, p. 12.
- Drozdov 2007, pp. 12–14.
- Duboin, A. (1902). "Les Romains ont-ils connu l'aluminium ?" [Did the Romans know about aluminum?]. La Revue scientifique (in French). 18 (24): 751–753.
- Pliny's Natural History. Translated by Rackham, H.; Jones, W.H.S.; Eichholz, D. E. Harvard University Press; William Heinemann. 1949–54. Archived from the original on December 29, 2016.
- Eggert, Gerhard (1995). "Ancient aluminum? Flexible glass? Looking for the real heart of a legend". Skeptical Inquirer. 19 (3): 37–40.
- Foster, Herbert Baldwin, ed. (1954). Dio's Roman History (PDF). Translated by Cary, Earnest (7 ed.). William Heinemann Limited; Harvard University Press. p. 173.
- Butler, Anthony R.; Glidewell, Christopher; Pritchard, Sharee E. (1986). "Aluminium Objects from a Jin Dynasty Tomb – Can They Be Authentic?". Interdisciplinary Science Reviews. 11 (1): 88–94. doi:10.1179/isr.19220.127.116.11.
- Drozdov 2007, p. 16.
- Clapham, John Harold; Power, Eileen Edna (1941). The Cambridge Economic History of Europe: From the Decline of the Roman Empire. CUP Archive. p. 207. ISBN 978-0-521-08710-0.
- Balston, John Noel (1998). "Appendix I – In Defence of Alum". The Whatmans and Wove Paper: Its Invention and Development in the West: Research Into the Origins of Wove Paper and of Genuine Loom-Woven Wirecloth. 3. John Balston. p. 198. ISBN 978-0-9519505-3-1.
- Setton, Kenneth Meyer (1976). The Papacy and the Levant, 1204–1571: The fifteenth century. American Philosophical Society. p. 239. ISBN 978-0-87169-127-9.
- Drozdov 2007, p. 17–18.
- Drozdov 2007, p. 25.
- Weeks, Mary Elvira (1968). Discovery of the elements. 1 (7 ed.). Journal of chemical education. p. 187.
- Richards 1896, p. 2.
- Drozdov 2007, p. 26.
- Drozdov 2007, p. 27.
- Pott, Johann Heinrich (1746). Chymische Untersuchungen, welche fürnehmlich von der Lithogeognosia oder Erkäntniß und Bearbeitung der gemeinen einfacheren Steine und Erden ingleichen von Feuer und Licht handeln [Chemical investigations which primarily concern lithogeognosia or knowledge and processing of common simple rocks and earths as well as fire and light] (in German). 1. Voss, Christian Friedrich. p. 32.
- Chisholm, Hugh, ed. (1911). "Alum". Encyclopædia Britannica (11 ed.). Cambridge University Press.
- Richards 1896, p. 3.
- Lennartson, Anders (2017). The Chemical Works of Carl Wilhelm Scheele. Springer International Publishing. p. 32. ISBN 978-3-319-58181-1.
- Wiegleb, Johann Christian (1790). Geschichte des wachsthums und der erfindungen in der chemie, in der neuern zeit [History of growth and inventions in chemistry in the modern time]. Nicolai, Christoph Friedrich. p. 357.
- Wurtz, Adolphe (1865). "An introduction to chemical philosophies, according to modern theories". Chemical News. 15: 99.
- Drozdov 2007, p. 31.
- Richards 1896, pp. 3–4.
- Richards 1896, p. 4.
- Guyton, Louis-Bernard (1795). "Expériences comparatives sur les terres, pour déterminer leur fusibilité, leur manière de se comporter avec les flux salins ou vitreux, et l'action dissolvante qu'elles exercent réciproquement les unes sur les autres" [Comparative experiments on the earth, to determine their fusibility, their behavior with the saline or vitreous flows, and the dissolving action they exert on each other]. Journal de l'École polytechnique (in French). 3: 299.
- Davy, Humphry (1812). "Of metals; their primary compositions with other uncompounded bodies, and with each other". Elements of Chemical Philosophy: Part 1. 1. Bradford and Inskeep. p. 201.
- Davy, Humphry (1808). "Electro Chemical Researches, on the Decomposition of the Earths; with Observations on the Metals obtained from the alkaline Earths, and on the Amalgam procured from Ammonia". Philosophical Transactions of the Royal Society. Royal Society of London. 98: 353. doi:10.1098/rstl.1808.0023.
- Quinion, Michael (2005). Port Out, Starboard Home: The Fascinating Stories We Tell About the words We Use. Penguin Books Limited. pp. 23–24. ISBN 978-0-14-190904-2.
- Royal Danish Academy of Sciences and Letters (1827). Det Kongelige Danske Videnskabernes Selskabs philosophiske og historiske afhandlinger [The philosophical and historical dissertations of the Royal Danish Science Society] (in Danish). Popp. pp. XXV–XXVI.
- Wöhler, Friedrich (1827). "Ueber das Aluminium" [About aluminium]. Annalen der Physik und Chemie. 2 (in German). 11: 146–161.
- Drozdov 2007, p. 36.
- Christensen, Dan Ch. (2013). "Aluminium: Priority and Nationalism". Hans Christian Ørsted: Reading Nature's Mind. OUP Oxford. pp. 424–430. ISBN 978-0-19-164711-6.
- Fontani, Marco; Costa, Mariagrazia; Orna, Mary Virginia (2015). The Lost Elements: The Periodic Table's Shadow Side. Oxford University Press. p. 30. ISBN 978-0-19-938334-4.
- Larned, Josephus Nelson (1923). The New Larned History for Ready Reference, Reading and Research: The Actual Words of the World's Best Historians, Biographers and Specialists; a Complete System of History for All Uses, Extending to All Countries and Subjects and Representing the Better and Newer Literature of History. C.A. Nichols Publishing Company. p. 4472.
- Richards 1896, pp. 4–5.
- Bjerrum, Niels (1926). "Die Entdeckung des Aluminiums". Zeitschrift für Angewandte Chemie. 39 (9): 316–317. doi:10.1002/ange.19260390907. ISSN 0044-8249.
- Drozdov 2007, p. 38.
- Holmes, Harry N. (1936). "Fifty Years of Industrial Aluminum". The Scientific Monthly. 42 (3): 236–239.
- Skrabec 2017, pp. 10–11.
- Lide, David R. (1995). CRC Handbook of Chemistry and Physics: A Ready-reference Book of Chemical and Physical Data. CRC Press. p. 4-3. ISBN 978-0-8493-0595-5.
- Laparra, Maurice (2015). A portrait of aluminium, metal of dream and modernity (PDF) (Report). Institute for the History of Aluminium. p. 3. Retrieved December 19, 2018.
- Venetski, S. (1969). "'Silver' from clay". Metallurgist. 13 (7): 451–453. doi:10.1007/BF00741130.
- Singh, R. V. (2011). Aluminium Rolling: Processes, Principles and Applications. Tata McGraw-Hill Education. p. 454. ISBN 978-0-07-070444-2.
- Drozdov 2007, p. 39.
- Sainte-Claire Deville, H. E. (1859). De l'aluminium, ses propriétés, sa fabrication [Aluminium, its properties, its manufacture] (in French). Mallet-Bachelier. Archived from the original on 30 April 2016.
- Skrabec 2017, p. 11.
- Drozdov 2007, p. 46.
- Skrabec 2017, p. 12.
- Drozdov 2007, p. 49.
- Binczewski, George J. (1995). "The Point of a Monument: A History of the Aluminum Cap of the Washington Monument". JOM. 47 (11): 20–25. doi:10.1007/bf03221302.
- Drozdov 2007, p. 41.
- McNeil 2002, p. 104.
- McNeil 2002, p. 103.
- Drozdov 2007, p. 42.
- Drozdov 2007, pp. 43–45.
- Howell, Georgina (2010). Gertrude Bell: Queen of the Desert, Shaper of Nations. Farrar, Straus and Giroux. pp. 4–5. ISBN 978-1-4299-3401-5.
- "Aluminum". Report on Mineral Industries in the United States at the Eleventh Census, 1890. U.S. Government Printing Office. 1892. pp. 280–281.
- McNeil 2002, p. 105.
- Geller, Tom (2007). "Aluminum: Common Metal, Uncommon Past". Distillations. Science History Institute.
- Drozdov 2007, p. 45.
- Skrabec 2017, p. 15.
- Netto, C. (1889). "Die Herstellung von Aluminium". Zeitschrift für Angewandte Chemie (in German). 2 (16): 448–451. doi:10.1002/ange.18890021603. ISSN 0044-8249.
- Drozdov 2007, p. 59.
- Drozdov 2007, pp. 52–53.
- Drozdov 2007, pp. 55–59.
- "Alusuisse" (in German). Historisches Lexikon der Schweiz. 2013.
- Sheller, Mimi (2014). Aluminum Dreams: The Making of Light Modernity. MIT Press. p. 41. ISBN 978-0-262-02682-6.
- Drozdov 2007, pp. 59–61.
- Drozdov 2007, p. 74.
- "Aluminium history". The History of Aluminium. RUSAL.
- Regelsberger, Friedrich F. (2013). Chemische Technologie der Leichtmetalle und ihrer Legierungen [Chemical Technologies of Light Metals and Their Impurities] (in German). Springer-Verlag. p. 13. ISBN 978-3-662-34128-5.
- "Aluminium history". All about aluminium. RUSAL.
- Drozdov 2007, p. 85.
- Drozdov 2007, pp. 64–69.
- Drozdov 2007, pp. 66–69.
- Schlesinger, Mark E. (2013). Aluminum Recycling (2 ed.). CRC Press. pp. 2–6. ISBN 978-1-4665-7025-2.
- Wallace, G. (2010). "Production of secondary aluminium". In Lumley, Roger. Fundamentals of Aluminium Metallurgy: Production, Processing and Applications. Elsevier Science. p. 70. ISBN 978-0-85709-025-6.
- "Aluminum. Supply-Demand Statistics". Historical Statistics for Mineral Commodities in the United States (Report). United States Geological Survey. 2017.
- Ingulstad, Mats (2012). "'We Want Aluminum, No Excuses': Business-Government Relations in the American Aluminum Industry, 1917–1957". In Ingulstad, Mats; Frøland, Hans Otto. From Warfare to Welfare: Business-Government Relations in the Aluminium Industry. akademika publishing. pp. 33–68. ISBN 978-82-321-0049-1.
- "Aluminium in transport". All about aluminium. RUSAL.
- Skrabec 2017, p. 79.
- Drozdov 2007, pp. 69–70.
- Drozdov 2007, pp. 165–166.
- Thorsheim, Peter (2015). Waste into Weapons. Cambridge University Press. pp. 66–69. ISBN 978-1-107-09935-7.
- Seldes, George (1943). Facts and Fascism (5 ed.). In Fact, Inc. p. 261.
- Skrabec 2017, p. 134–135.
- Davis, Brian L. (2012). The German Home Front 1939–45. Bloomsbury Publishing. p. 31. ISBN 978-1-78096-806-3.
- Sokolov, Boris V. (2007). "The role of lend‐lease in Soviet military efforts, 1941–1945". The Journal of Slavic Military Studies. 7 (3): 567–586. doi:10.1080/13518049408430160. ISSN 1351-8046.
- Chandonnet, Fern (2007). Alaska at War, 1941–1945: The Forgotten War Remembered. University of Alaska Press. p. 338. ISBN 978-1-60223-135-1.
- Weeks, Albert Loren (2004). Russia's Life-saver: Lend-lease Aid to the U.S.S.R. in World War II. Lexington Books. p. 135. ISBN 978-0-7391-0736-2.
- Drozdov 2007, p. 135.
- The Evolution of Aluminum Conductors Used for Building Wire and Cable (PDF) (Report). National Electrical Manufacturers Association. 2012.
- Nappi 2013, pp. 5–6.
- Nappi 2013, p. 9.
- Bockris, John (2013). Comprehensive Treatise of Electrochemistry: Electrochemical Processing. Springer Science & Business Media. p. 303. ISBN 9781468437850.
- United States Environmental Protection Agency (1973). The Cost of Clean Air. United States Government Printing Office. pp. IE-87.
- Nappi 2013, pp. 12–13.
- Nappi 2013, pp. 9–10.
- Nappi 2013, p. 7.
- Nappi 2013, p. 3.
- Nappi 2013, p. 10.
- Nappi 2013, pp. 14–15.
- Nappi 2013, p. 17.
- Nappi 2013, p. 20.
- Nappi 2013, p. 22.
- Nappi 2013, p. 23.
- Nappi 2013, p. 15.
- Drozdov, Andrey (2007). Aluminium: The Thirteenth Element. RUSAL Library. ISBN 978-5-91523-002-5.
- McNeil, Ian (2002). An Encyclopedia of the History of Technology. Routledge. ISBN 978-1-134-98165-6.
- Nappi, Carmine (2013). The global aluminium industry 40 years from 1972 (PDF) (Report). International Aluminium Institute.
- Richards, Joseph William (1896). Aluminium: Its history, occurrence, properties, metallurgy and applications, including its alloys (3 ed.). Henry Carey Baird & Co.
- Skrabec, Quentin R. (2017). Aluminum in America: A History. McFarland. ISBN 978-1-4766-2564-5.