HOERNESITE

ˈhərnəˌsīt, ˈhȯr- noun

( -s )

Etymology: German hörnesit, from Moritz Hoernes died 1868 Austrian paleontologist + German -it -ite

: a mineral Mg 3 As 2 O 8 .8H 2 O consisting of hydrous magnesium arsenate occurring as crystals resembling gypsum