#declare Retaw = texture {
  pigment {
    gradient y
    color_map {
      [0 0.1 color Aquamarine color Turquoise]
      [0.1 0.5 color White color White]
      [0.5 0.9 color Turquoise color White]
      [0.9 1.0 color White color rgbf <1, 1, 1, .8>]
    }
  }
  finish { reflection .4 phong 1}
}
