This is a pair of vintage Japanese cups of Utsutsugawa ware, which was made by one of the greatest potter, the 13th Gagyu Yokoishi, who was designated as a human important intangible cultural asset in 1975. These were made about - 50 years ago. The signature of the potter is written on the bottom. Utsutsugawa ware was started by 1st Gagyu Yokoishi founded in 1692 in the Isahaya domain in Hizen. Porcelain-like and thinly potted, Utsutsugawa is made of extremely fine-grained mountain clay fairly high in iron content.