Successful modern-day architecture now demands more than just a particularly straight-edged design. Current trends in architecture focus on intelligent building technology for interiors. And the focus for exteriors is on a state of the art outer building skin that breathes by using natural materials. In a much sought after manner, Riegel 50 combines the archaic impression of blue reduction firing, or a subdued sinter patina effect, with the elegant simplicity of the special long format.