The Origin of KO-KUTANI Porcelain—Part II: The Unearthed Secrets of the Hakuji Shallow Bowl

The present work aims at completing our previous comprehensive study on Ko-Kutani ware through the analysis, for the first time ever, of the renowned Hakuji bowl (white porcelain shallow bowl) excavated at the Noborigama kiln site in Kaga. The bowl had never been made available for such a purpose prior to this study owing to its absolute rarity, exceptional importance and fragile condition. Its shape and potting techniques, along with its materials, enabled both a direct comparison with the magnificent Ko-Kutani masterpieces belonging to the Ishikawa Prefectural Museum of Art collection and the groundbreaking identification of a definitive firing timeline marked by two distinct production stages: the Pre-Hakuji and Post-Hakuji phases. The crucial influence of the Hakuji bowl on Ko-Kutani production as a whole has been revealed for the first time ever, providing unprecedented and definitive evidence of the origin of the renowned and iconic porcelains. In consideration of the strict requirements and the absolute prohibition to sample or even touch any of the works of art, portable Energy-Dispersive X-Ray Fluorescence spectroscopy (pED-XRF) was selected as the most suitable technique for the type of materials to be investigated.