Hoshino enhances the intensity by his use of black-fire (kokuto), a carbonising process, first reproduced in Japan in the 1960s. It is a technique widely used by avant-garde ceramists in Japan to add monumentality, while negating decoration and colour. As well as avoiding the accidental or obfuscating effects of glaze, the technique references historical pottery found on archaeological sites. Hoshino’s lustrous finish is induced by his use of pine needles for the kokuto process. They are introduced at the end of the firing in an electric kiln.