It’s much more logical than Aluminium. It was originally extracted from Alum so it became Aluminum.
But the British got prissy over it and added an extra in to it.
The American pronunciation is far more sensible than ours.
Not entirely true - in either count. The "ium" ending is almost universally used when taking a name of something, and adding a syllable to make the element name; and this was all because in the early 19th Century consensus was reached around naming scheme. Aluminium is not named from Alum, but Alumina - and originally was called that, then alumium, then alumine. Davey didn't change his mind until 1812 years later, trying to call it aluminum - a year after "Aluminium" became first used in a paper in Britain. So Aluminium *was* actually used first; then Davey was able to change peoples minds (as he was a better known scientist) for a bit, before it was changed back to the original use outside of America - it had nothing to do with "the British got prissy over it and added an extra in to it" as it had the "i" in for a year before aluminum was ever used as a word!
And you will note - that Davey's first choice to call it was allium - due the agreement that most elements should end "ium" - which gives better credence to the "aluminium" being more in line with the standard naming scheme.
For reference, there are only 4 elements (vs 70+) that end "um" and not "ium", and none of them have "um" instead of "ium" from English etymology - for both Tantalum & Lanthanum it is because they swapped the "s" out (Tantalus/Lanthanum), and for Platinum/Molybdenum it was a Spanish/Greek word being pluralized.
