alumian
/əˈl(j)uːmɪən/Mineralogy. Now disused
noun
A white mineral originally thought to consist of aluminium sulphate and now identified with natroalunite.
Origin
Mid 19th century; earliest use found in American Journal of Science. From German Alumian from Alum- (in classical Latin alūmen) + -ian, after German Alumia, former alternative name for alumina.