English chemist Humphry Davy originally named the element aluminum after the mineral alumina and later changed it to aluminum. Other chemists felt the name did not conform to the -ium suffix of other element Davy named. No standard was set and both spellings, aluminum and aluminium appeared in scientific journals throughout the 19th Century. In the United States, the -ium spelling was dominant and appeared in Webster's Dictionary in that form.
In 1888, Hall was advertising his new technique and created a handbill describing his methods that used the -um spelling. It is generally believed this was an accidental misspelling and his process was so revolutionary that the spelling stuck in the American press and people who began working with the metal. By 1926, the American Chemical Society officially adopted aluminum as the 'proper' spelling in their publications.
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