ə|lümōˌhīdrōˈkalˌsīt, |alyə(ˌ)mō- noun
Etymology: International Scientific Vocabulary alumo- (from aluminum) + hydr- + calcite
: a mineral consisting of a hydrous calcium aluminum carbonate CaAl 2 (CO 3 ) 2 (OH) 4 .2H 2 O and occuring as white chalky radiating masses