Artists have a wide range of materials to use in their creations. Experimenting with different forms of art styles and mediums has been a way to stretch an artist’s experience. There are painters who have tried sculpting in clay to create a new way to express their vision of the world. Other artists have chosen to make glass art when their main focus was always flat graphics such as pencil sketches. All of these changes help artists to grow. Combining different types of elements makes artists grow in new ways. Historical examples of this are found in early Mesopotamian murals. Rocks, seashells and bits of ivory were combined to create pictures within their murals.