Hi Jim,
The background consist of polystyrene which I carved in many angles en curves. Then a layer of a kind of concrete (used to paste tiles in the bathroom (tile adhesive??)) which I painted in a natural colour. Afther that a layer of epoxy resin was put on the background in combination with sand, so the background will not shine that much.
Hopefully you will understand it. English is not my native language.
Greetz Sjaak