Activa CelluClay Instant Papier Mache White 1 lb. Papier Mache is a versatile sculpting medium wonderful for arts and crafts sculpture and design projects. With CelluClay Instant Papier Mache you simply add water for a safe-to-use sculpting medium without the hassle of mixing or using strips of paper. Celluclay will adhere to almost any surface and can be sawed sanded or nailed when dry.