Jack is particularly recognised for working in porcelain, a complex medium known for its delicate fineness and translucent nature. Whilst enjoying the soft sensual qualities of the clay, the purity of the whiteness accentuates the simplicity of form with minimal adornment or decoration. Porcelain is, by reputation, the most difficult and capricious clay to work with making demands on the sensitivity and skill of the maker.
The serrated mark is a distinguishing feature in Jack's work adding a distinct focal point to each piece. This gesture in the clay indicates a full stop, a more forceful slash, or a gentle kiss to alter the profile from becoming too perfect. These signature marks are made from broken pottery tools and scavenged shoreline objects such as broken shells, rusty iron and driftwood.