A kuro Raku chawan made by Raku Ryōnyū了入 IX, bearing authentic period calligraphy and seal indicative of the 9th head of the Raku family. It represents a significant example of Edo-period tea ceramics and holds cultural value in the context of Japanese tea ceremony traditions.

This work is attributed to Raku Ryōnyū了入 IX (1745–1834), the ninth-generation head of the Raku family. Ryōnyū了入 IX was active during the late Edo period and is known for preserving traditional Raku techniques while subtly refining the form and glaze of Raku chawan.

His works are valued for their deep black glazes, warm modelling, and close connection to the tea aesthetics upheld by the Urasenke and Omotesenke tea schools during that period.