horn·blende 
(hôrnblĕnd′)
(hôrnblĕnd′)n.
The most common mineral in the amphibole group, CaNa(Mg,Fe)4(Al,Fe,Ti)3Si6O22(OH,F)2 commonly green to black, found in igneous and metamorphic rocks.
[German : Horn, horn (from Middle High German, from Old High German; see ker-1 in the Appendix of Indo-European roots) + Blende, blende; see BLENDE.]