Green mud amphibolite schist is a metamorphic rock formed by regional metamorphism, including basalt, tuff, gabbro, diabase, and other rocks. It represents a metamorphic environment of about 500-600 degrees Celsius and a pressure of less than ten kilobars. Its main minerals are chlorite and amphibole, with amphibole content greater than 40%. It may also contain small amounts of minerals such as plagioclase, epidote, biotite, pyrite, etc. Green mudstone, dark green in color, carved into small pieces with a small knife to appear light green, extremely fine and scaly. Hornstone schist is a common rock in orogenic belts and ancient metamorphic terrains, and is a characteristic feature of regional metamorphic amphibolite facies.