'Volborthite' definitions:

Definition of 'Volborthite'

From: GCIDE

Volborthite \Vol"borth*ite\, n. [So named after Volborth, who first discovered it.] (Min.) A mineral occurring in small six-sided tabular crystals of a green or yellow color. It is a hydrous vanadate of copper and lime. [1913 Webster]