Check your periodic table

Last night I mentioned something about aluminum cans in conversation and they responded, "You mean aluminium?" No, I meant aluminum. I thought she must have been joking.

It turns out aluminum is spelled and pronounced aluminium in most other countries besides the US. Again, thanks to Wikipedia I have learned that both spellings are acceptable but aluminium is the preferred spelling. (Even though it shows up as an incorrect spelling on my spell-checker!)

It took me 2 years to discover that and it blew my mind.