Hornblendite is a plutonic rock consisting mainly of the amphibolehornblende. Hornblende rich ultramafic rocks are rare and when hornblende is the dominant mineral phase they are classified as hornblendites with qualifiers such as garnet hornblendite identifying a second abundant contained mineral.Metamorphic rocks composed dominantly of amphiboles are referred to as amphibolites.
See more at Wikipedia.org...