// linear prism in z-direction: from ,to ,number of points (first = last)
prism { -1.00 ,1.00 , 4
       <-1.00, 0.00>,  // first point
       < 1.00, 0.00>, 
       < 0.00, 1.50>, 
       <-1.00, 0.00>   // last point = first point!!!!
       rotate<-90,0,0> scale<1,1,-1> //turns prism in z direction! Don't change this line! 

       texture { pigment{ color White} 
                 finish { phong 1.0}
               } // end of texture

       scale <1.00, 1.00, 1.00>
       rotate<0,0,0> 
       translate<0.00, 0.00, 0.00> 
     } // end of prism --------------------------------------------------------

