/usr/share/gwyddion/glmaterials/Green-Plastic is in gwyddion-common 2.44-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 | Gwyddion resource GwyGLMaterial
0.0 0.0 0.0 1.0
0.1 0.35 0.1 1.0
0.45 0.55 0.45 1.0
0.0 0.0 0.0 1.0
.25
|