union{ //-----------------------------------

//#for(Identifier, Start, End [, Step]) 
 #for (NrX, 0, 4, 1) // outer loop 
  #for (NrY, 0, 4, 1) // middle loop 
   #for (NrZ, 0, 4, 1) // inner loop
    
     sphere{ <0,0,0>,0.4
             translate< NrX*1, NrY*1, NrZ*1> 
  
             texture{ pigment{ color rgb<1.0,0.1,0.20>*1}
                      finish { phong 1 reflection { 0.4 metallic 0.5} }
                    }
    } 
   #end // ------------- end z of #for outer loop 
  #end // ------------- end y of #for middle loop 
 #end // ------------- end x of #for inner loop 

rotate<0,0,0> 
translate<0,0,0>
} // end of union --------------------------