|Prussian blue, synthetic pigment known as bero-ai was introduced to Japan in the late Edo Period. It is said
that a merchant of Edo, Mizuhoya, Shimizu Usaburo who participated in the Paris Exposition of 1867 and
brought back a cobalt pigment. It was tested and successfully used by Hattori Kyoho to decorate his
Lord Nabeshima of Saga, also interested in new coloring method and he invited both Usaburo and Kyoho to
Arita hoping to improve the porcelain industry of his region in 1869.
This process was further innovated in 1870, with the help of German chemist, Gottfried Wagener (1831-
8192) and the synthetic cobalt blue had become in common use at the factories of the region.
The under glaze blue decoration of the early Meiji period, has a distinctive bright hue and by comparing to
the natural gosu blue color, it appears to be more harsh and shallow. Especially earlier examples show the
maker’s difficulties in techniques with blotchy brush works, smudges and uneven color runs .