Clinker is a waste product that forms on the crucible beneath a metal forge. It is composed of coke and other impurities which form in the process of iron making. We have a blacksmith in Wakefield who is collecting large amounts of this for us to use in a sculpture. The overall form of the piece will include a pinnacle which will reference a ‘column of coal’ which was said to exist beneath the cathedral. The structure will be built up in areas on the surface as well as imitating a system of mining called ‘stoping’. There will also be reference to the way that rock forms in its layering.