Furniture Design 5x5 Chair by Barbara Princic The 5x5 chair is a typical design project where the limitation is recognised as a challenge. The chair's seat and the back are made of xilith which is very difficult to be shaped. Xilith is the raw material that can be found 300 meters under the ground's surface and is comined with a coal. Currently the majority of the raw material is thrown away. From environmental point of view this material generates waste on the earth's surface. Therefore the idea about the chair design seemed to be very provocative and challenging.