tetrahedronFaces :: [[Int]]
tetrahedronFaces = [ [0,2,1]
                   , [0,1,3]
                   , [0,3,2]
                   , [1,2,3]
                   ]
tetrahedronFaces :: [[Int]]
tetrahedronFaces = [ [0,2,1]
                   , [0,1,3]
                   , [0,3,2]
                   , [1,2,3]
                   ]
tetrahedronFaces = [ [0,2,1]
                   , [0,1,3]
                   , [0,3,2]
                   , [1,2,3]
                   ]