Some rocks according to their use or texture are classified into different types. Know more about Amphibolite Texture and Conglomerate Texture. Types of Amphibolite are Hornblendite whereas the types of Conglomerate are Not Available.During historic times, some rocks depending on their hardness were used to create Pictographs and Petroglyphs. Rocks which are hard were generally not used. Pictographs are paintings or drawings that have been placed or created on the surface of rock. Amphibolite was not used to create pictographs whereas Conglomerate is used to create pictographs. Petroglyph is an image which is carved into a rock. These are images created by removing part of a rock surface by incising, picking, carving or abrading, as a form of rock art. Amphibolite was not used to create petroglyphs whereas Conglomerate was used to create petroglyphs.