syngenite
noun
syn·ge·nite
ˈsinjəˌnīt
plural -s
: a mineral K2Ca(SO4)2.H2O consisting of a hydrous calcium potassium sulfate and occurring in colorless or white tabular crystals (hardness 2.5, specific gravity 2.6)
Word History
Etymology
German syngenit, from Greek syngenēs related + German -it -ite; from its relationship to polyhalite