gamsigraditeMin.|ˈgæmsɪˌgrædaɪt| [f.Gamsigrad in Serbia, where it is found + -ite.] A velvet-black variety of amphibole. 1862Amer.Jrnl.Sc.Ser. ii. XXXIV. 213 Breithaupt has given the name gamsigradite to a black hornblende, from Gamsigrad, in Servia.1864in Watts Dict.Chem. II. 771.