Chlorite schist is a type of schist that contains appreciable quantities of a chlorite. Chlorites are a group of pervasive silicate minerals that are usually produced as alteration products of other minerals. Thus, they are widespread in rocks formed through metamorphism. Chlorites are typically green in color and often bestow this hue to the rocks in which they are contained. Chlorite schists, therefore, are characteristically olive or jade-like in color and in some areas are known as greenschists. In China, small pieces of these rocks are utilized for medical purposes, especially as a treatment for excessive phlegm.