Jonathan Clarke’s production process uses the inventive sand-cast polystyrene technique, first developed by his father, Geoffrey Clarke in the late 1950s. Rejecting the more traditional method of creating a clay mould, which can then be reused to make multiple editions, Geoffrey took advantage of the properties of polystyrene to create models that would evaporate once in contact with the molten metal. This results in entirely unique sculptures that can never be replicated. It was at this time too that he moved away from using metals such as bronze and iron, in favour of aluminium: a lighter, more flexible metal with a lower melting point.
The ‘lost polystyrene’ method adopted by Jonathan means that each cast is a unique, one-off sculpture. He slices through a block of polystyrene with a hot wire, carving individual components with which to assemble the finished piece. The polystyrene is then buried in special moulding sand before the pure, molten aluminium is poured in. The polystyrene mould is instantly vaporised, leaving the aluminium cast to solidify in the sand.