newmtl mat23
  Kd 0.10 0.10 0.10

newmtl mat21
  Kd 1.00 1.00 1.00

newmtl mat18
  Kd 1.00 0.80 0.53

newmtl mat3
  Kd 0.50 0.87 0.92

newmtl mat1
  Kd 0.61 0.15 0.69