noun
also cu·men·geite kyüˈmenˌjīt, -ˌgīt
( -s )
Etymology: German cumengit, from Édouard Cumenge died 1902 French mining engineer + German -it -ite
: a mineral Pb 4 Cu 4 Cl 8 (OH) 8 .H 2 O consisting of a basic lead-copper chloride occurring in deep blue tetragonal crystals