Colcothar
Pronunciation : Col"co*thar
Part of Speech : n.
Etymology : [NL. colcothar vitrioli, fr. Ar. qolqotar.] (Chem.)
Definition : Defn: Polishing rouge; a reddish brown oxide of iron, used in polishing glass, and also as a pigment; -- called also crocus Martis.
Source : Webster's Unabridged Dictionary, 1913