Iron tsuba of oval form with the motif of horse trappings in openwork (sukashi). Copper sekigane. Iron bones (tekkotsu) on the rim.
Size: 80.4 x 75.8 x 5.2 mm
NBTHK Certificate №454567, allegedly saying that it is Akasaka School, Muromachi period.
A look-a-like tsuba in Robert. E. Haynes Catalog #7, 1983 on page 57 under №48 is described as follows:
"A masterpiece second period Owari sukashi tsuba. The plate is of beautiful color and quality almost like velvet. The design is very hard to discern, it might be the horse trappings, or even a moon. The style and type of Owari tsuba shows the great tradition of the Momoyama period and why it was the renaissance in time, as well as the arts produced, through the long history of all Japanese art. Ca. 1580. Ht. 7.7 cm, Th. (center) 5.5 mm, (edge) 5.25 to 5.75 mm."
Robert. E. Haynes Catalog #7, 1983, p. 57, №48.
I believe we can safely attribute this tsuba to Owari School, c. 1580.