角闪石是角闪石系列矿物的总称，根据其晶体结构可以被分为斜方角闪石和单斜角闪石两种。角闪石是含有氢氧根的链状结构硅酸盐。

角闪石于变质岩及火成岩中极普遍存在，多由富含铁镁矿物的岩石变质而成，在作用发生时，常有硅铁镁等物质加入。

颜色为深绿至黑色，其化学成分不定，常随其母岩之类别而改变，角闪岩常具片理及线构造，依其构造可分为：

1. 粗粒种 等粒、片理不明显外观颇似辉长岩
2. 中粒种 等粒、片理显著
3. 细粒种 等粒、片理甚发达
4. 斑状种 含斜长石变斑晶

Amphibole /ˈæmfᵻboʊl/ is the name of an important group of generally dark-colored, inosilicate minerals, forming prism or needlelike crystals, composed of double chain SiO
4 tetrahedra, linked at the vertices and generally containing ions of iron and/or magnesium in their structures. Amphiboles can be green, black, colorless, white, yellow, blue, or brown. The International Mineralogical Association currently classifies amphiboles as a mineral supergroup, within which are two groups and several subgroups.