Aluminum or Aluminium?

The chemical element classified on the Periodic Table with the atomic number 13 and symbol Al is a ductile, malleable silver-white metal. This metal is ubiquitous, being used in packaging, automotive, energy, construction, transportation, energy, aerospace, and defense applications, but there is a fascinating ambiguity with its official name in English. This is because it is goes by both aluminum and aluminium.

The modern distinction between these two terms is clear: aluminum is correct in American English, as well as Canadian English, while aluminium is correct in British English, as well as most other forms of English. The variability between these mutually intelligible languages should come as no surprise, as, due to linguistic rules endemic to the two nations, there are some 4,000 words used differently between the UK and the United States (e.g. aeroplane/airplane, aesthetics/esthetics, colour/color).

However, the exact origin of these names may come as a bit of a surprise, as the differences between the two were not solidified until the Twentieth Century. For the most part, Noah Webster’s An American Dictionary of the English Language established many discerning differences between words in British and American English in the Nineteenth Century. This generally simplified the language for the residents of the young United States, as Webster set forth many of the changes between the two languages that we see today and proposed some that obviously didn’t stick, such as changing tongue to tung.

In Webster’s 1828 dictionary, there was only one word offered for the atomic element Al: aluminum. This certainly helped advance the wording in the United States, but it was not the origin of the shorter word for the metal.

When Sir Humphry Davy discovered the element in the early Nineteenth Century, he initially named it alumium, but this version clearly didn’t catch on, not even with himself. This name he derived from alumina, a mineral that only had been named in English less than twenty years prior and was borrowed from the French alum, a white mineral used since antiquity for dyeing and tanning. However, he soon changed it to aluminum, before adjusting it once more to aluminium in 1812. Therefore, aluminum came before aluminium.

However, Davy’s final decision was the preference of his classically educated scientific colleagues from the get-go, as it possessed more of a classical ring and even aligned harmonically with many other elements that he personally had named, such as potassium, sodium, and magnesium. The spelling with –um continued somewhat in Britain for a while, but –ium soon took hold as the predominant form.

In the United States, however, the domination of aluminum took some time. Even though it was the only wording of the element offered in Webster’s Dictionary, aluminum appeared about as often as aluminium throughout the Nineteenth Century, with the –ium version actually being more common in American newspapers in the final decade of that century. However, the following decade, there was a reversal, in which the –um version began to take over.

This process may be tied to the emergence of aluminum as a viable product. In fact, neither aluminum nor aluminium would have been encountered at any substantial frequency throughout the 1800s; it was so hard to extract from its ores that the metal remained exotic and expensive, a rarity more precious than gold or silver. When Emperor Napoleon III had aluminum cutlery made for state banquets, a new process improved the extraction process, but the metal still cost more than gold.

Around the turn of the century, the availability and production of Al rapidly burgeoned, and one can ascertain that this is where the complete shift to –um occurred. As standards are always important, a shared word for the chemical element with thirteen protons in its atomic nucleus was integral. And, for clarification, journalists and even scientific minds would turn to the official source of American English: Webster’s Dictionary. Here they would find only aluminum, reaffirming it as the official term. In 1925, the American Chemical Society officially adopted it, likely in response to this shift.

An inherent purpose of standardization is to provide information with clarity, and this knowledge generally serves to enhance the safety and efficiency of industrial processes. Therefore, it may almost seem that using two similar words to describe aluminum/aluminium may be antithetical to this idea. However, the interchangeability of these two words is obvious, and generally, only one is chosen.

For example, standards published by the Aluminum Association and the American Welding Society (AWS), both of which are based in the United States, use aluminum (e.g. ANSI H35.2-2017: American National Standard Dimensional Tolerances for Aluminum Mill Products and AWS D1.2/D1.2M:2014 – Structural Welding Code – Aluminum). Alternatively, international standards published by ISO, being published in Geneva, Switzerland, favor aluminium (e.g. ISO 13832:2013 – Aerospace – Wire, aluminium alloy and copper-clad aluminium conductors – General performance requirements).

Ultimately, both aluminum and aluminium are correct, depending on the writer and the intended reader, and this differentiation in no way impedes the production of one of the most prominent metals in the world.