Mridangam is the name for the ancient drum which is made with a clay body. There were three shapes. This is all described clearly in natya sastra. South Indian "mridangam' is not made of clay any longer and is not actually mridangam - in name only. However this Mridanga is not only still clay but still retains the shape of the haritaki fruit as stated in natya sastra as being associated with vishnu. namami