Types of Hyaloclastite and Nepheline Syenite
Some rocks according to their use or texture are classified into different types. Know more about Hyaloclastite Texture and Nepheline Syenite Texture. Types of Hyaloclastite are Welded tuff, Rhyolitic tuff, Basaltic tuff, Trachyte tuff and Andesitic tuff. whereas the types of Nepheline Syenite are Borolanite and Litchfieldite.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. Hyaloclastite and Nepheline Syenite were used for creating 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. Hyaloclastite and Nepheline Syenite were used for creating petroglyphs.