Pronunciation: [stˈɪbi͡əm] (IPA) 
The word Stibium is a Latin term used to describe antimony, a chemical element. The word's spelling is quite straightforward, with the "s" and "t" pronounced as they are in English. The "i" in the first syllable is pronounced as "ih," and the "u" in the second syllable is pronounced as "yoo." The final "um" is pronounced as "uhm." When spoken aloud using the International Phonetic Alphabet, the word looks like /ˈstɪ.bi.əm/.
Antimony; stibnite.
Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874.
The word "Stibium" has its origins in Latin. It is derived from the Latin term "stibium" or "stimmi", which is shortened from "stibium nigrum" meaning "black antimony". "Stibium" refers to the metallic element antimony, known for its black or bluish-black color. The word has further roots in Greek, where "stibi" was used to describe various black substances including antimony. Ultimately, the term's origin is uncertain, but it is thought to come from an Egyptian source, as evidence suggests that antimony was used by the ancient Egyptians as early as 3100 BCE.
