ˈglȯkəˌfān noun
( -s )
Etymology: German glaukophan, from glauk- glauc- + -phan -phane
: a mineral Na 2 (Mg,Fe) 3 Al 2 Si 8 O 22 (OH) 2 consisting of a blue, bluish black, or grayish silicate of sodium, aluminum, iron, and magnesium occurring in certain crystalline schists