I'm not even sure why I am doing this, but:
Antimony is the Element 51
Geology: Antimonite is Stibnite and Stibnite is Antimony.
Chemistry: Antimonite is a mineral of Antimony, a salt in fact, which can have a couple of different compounds.
Don't even go down the path of Antimonites and Antimonates....
Antimony is one of the weird ones I retained from Highschool chemistry, possibly due to the difference between the compounds in Chemistry vs Geology, and not spoken of again until the great Antimony Rush of 2024.
(20min delay)