tiemannite
noun
tie·mann·ite
ˈtēməˌnīt
plural -s
: a mineral HgSe that is a native mercuric selenide and occurs commonly in dark gray or nearly black masses of metallic luster (specific gravity 8.2–8.5)
Word History
Etymology
German tiemannit, from W. Tiemann, 19th century German scientist who discovered it + German -it -ite