#declare Rust =
texture {
    pigment {
        granite
        color_map {
            [0.0 rgb <0.89, 0.51, 0.28>]
            [0.4 rgb <0.70, 0.13, 0.00>]
            [0.5 rgb <0.69, 0.41, 0.08>]
            [0.6 rgb <0.49, 0.31, 0.28>]
            [1.0 rgb <0.89, 0.51, 0.28>]
        }
    }
    finish { ambient 0.2 diffuse 0.4 }
}