Believe it or not, aluminium was once considered more precious than gold and silver. Although today aluminium is ubiquitous, making up about 8% of the Earth’s crust and used in everything from soda cans to aeroplanes, this metal was once a rare commodity that commanded prices higher than gold.
Early Understanding of Aluminium
Compounds The earliest reported identification of an aluminium compound was in 1761 by the Swedish chemist Carl Wilhelm Scheele, who isolated alumina (aluminium oxide) from the mineral bauxite, though he believed it to be a new elemental “earth” rather than a compound (Liu & Golab, 2003).
The Danish physicist Hans Christian Ørsted first produced metallic aluminium in 1825 through chemical reduction, yielding small amounts of impure metal (Schlesinger, 2015). Understanding of aluminium chemistry gradually improved, though isolation methods were inefficient for bulk production.
Early Applications and Value
In the early to mid-19th century, aluminium’s rarity lent it novelty, value, and scientific interest. The French Emperor Napoleon III reportedly reserved his limited aluminium cutlery and tableware for esteemed guests, preferring to dine on gold and silver himself (Guilbert, Park, & Lambert, 1985).
Napoleon III also notably constructed an aluminium obelisk in Paris rather than the traditional stone, further indicating aluminium’s prestige (Richards, 1896). By the mid-1850s to early 1860s, aluminium commanded prices estimated between $1,200-2,000 per kilogram, over twice the ~$664/kg price of gold then (Richards, 1896; Schlesinger et al., 1953). Such high-value restricted applications demonstrated aluminium’s perceived worth.
Development of Modern Aluminium Production Methods
Aluminum remained prohibitively expensive until two researchers independently devised improved production methods in the late 19th century. In 1886, American Charles Martin Hall and French scientist Paul Héroult both patented essentially identical electrolysis techniques to extract aluminum from alumina, now known jointly as the Hall-Héroult process (Liu & Golab, 2003).
This revolutionary method facilitated greatly increased yields at higher purities and lower costs. By 1890, aluminum prices had already declined to ~$4.50/kg with the new process (Schlesinger et al., 1953). Continuing innovations in electricity supply, electrode technology, and extraction equipment dropped aluminum prices throughout the 20th century to modern values around $2/kg (International Aluminium Institute, 2020).
The Hall-Héroult method has enabled the vast escalation of aluminum production in the past century, from negligible tonnages in 1880 to ~64 million metric tons in 2020 (U.S. Geological Survey, 2021). Other metals and materials have also transitioned from rarity to abundance with improved separation technologies.
Conclusion
Once considered a precious metal, aluminum has become ubiquitous due to 20th century advances allowing extensive production from bauxite ore. Similar material journeys from rare to common occur continually; for example, high-purity silicon for electronics faced comparable cost barriers before the Siemens process reduced prices 1000-fold (Liu & Golab, 2003).
Historical analyses clarify how scientific innovations transform material supply and applications over time. Further technology developments may yield an abundance of additional metals also presently rare or expensive.
