isosurface{ // ------------------------------------------------------------

  function { sqrt(x*x + y*y + z*z) - 0.8
             + sin(0.5*sin(y*4))*0.1
           }

  threshold 0
  accuracy 0.0001
  max_gradient 5
  contained_by {box {<-1,-1,-1>, < 1, 1, 1>}}

  texture { T_Stone8
            //pigment{ color rgb<1,0.85,0.45>}
            finish { specular 0.2 phong 0.4 }
	  }
  scale <0.80,1.00,0.80>*1.4
  rotate <0,0, 0>
  translate <-0, 1.2, 0>
} // end of isosurface -----------------------------------------------------