角闪石岩是一种超镁铁岩石，主要是由角闪石组成，含量超过90%，成分包含钠、钙、镁、铁、铝、硅等氧化物和氢氧化物。也有时含有少量的辉石和橄榄石，伴生的矿物主要有含钒的钛磁铁矿。

Hornblendite is a plutonic rock consisting mainly of the amphibole hornblende. 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.