       texture{pigment{color rgb<0.55,0.85,0.85> }
                 normal {pigment_pattern{radial frequency 25 //sine_wave
                                         color_map {[0.0, rgb 0]
                                                    [0.1, rgb 1]
                                                    [0.9, rgb 1]
                                                    [1.0, rgb 0]}
                                         rotate< 90,0,0> scale 0.5} 4}
               finish { phong 1 reflection 0.2}
               } // end of texture ---------------------------------------------------
