texture{ pigment{ color rgb<0.25,0.55,0.15> }
                 normal { radial poly_wave frequency 25 
                          scale 1.0  turbulence 0.25 rotate< 0,0,0>}
                 finish {  phong 0.5 phong_size 5  reflection 0.0}
                 rotate<90,0,0>
               } // end of texture ---------------------------