Ah, a militant Aluminist... Take a look at the periodic table. Almost all elements with a -um ending are actually -ium, especially the metals. Exceptions exist such as Molybdenum, Tantalum, etc, but they are few....
Etc through the periodic table. The general rule is that atomic names end in -ium, and only vary when the name is a 'common' name like Copper, derived from the Latin 'Cuprum' Aluminium actually fits the naming system better than 'Aluminum'. But of course America sets and breaks all the rules at will. We are all supposed to follow them.......