NATCON

1. masonry: constructed of brick or stone.
2. concreted: constructed of concrete, a material made of sand and gravel that is united by cement into a hardened mass used for roads, foundations, etc. (adapted from the Illustrated Contemporary Dictionary, Encyclopaedic Edition, 1978)
3. loose boulders: constructed from large stones or blocks of concrete, often placed loosely for protection against waves or water turbulence.
4. hard surface: constructed with a surface of hard material, usually a term applied to roads surfaced with asphalt or concrete.
5. unsurfaced: constructed with no extra protection, usually a term applied to roads not surfaced with a hard material.
6. wooden: constructed from wood.
7. metal: constructed from metal.
8. glass reinforced plastic (GRP): constructed from a plastic material strengthened with fibres of glass.
9. painted: the application of paint to some other construction or natural feature.