Gymnite is an amorphous form of antigorite. There is also antigorite and steatite here. Antigorite and lizardite are the polymorphs with platy habit. Lamellated antigorite occurs in tough, pleated masses. There are three important mineral polymorphs of serpentine&colon; antigorite, chrysotile and lizardite. Antigorite contains 13 wt.% water and therefore causes substantial mantle melting. Antigorite contains water in its structure, about 13 percent by weight.