newmtl mat12
  Kd 1.00 0.92 0.23

newmtl mat23
  Kd 0.10 0.10 0.10

newmtl mat17
  Kd 0.27 0.35 0.39

newmtl mat22
  Kd 0.62 0.62 0.62

newmtl mat21
  Kd 1.00 1.00 1.00