Ko-kinko ymagane cast tsuba of oval form with chiseled diaper pattern of double head waves on both sides and a rabbit cast and carved with its eye inlaid in yellow metal (gold or brass) on the face. Fukurin which holds together the sandwiched layers of metal (sanmai) is about 2.7 mm wide. Possibly, early Mino (ko-Mino) school. Size: 66.6 x 59.9 x 4.0 mm. Some connoisseurs believe that this kind of tsuba was in mass production at the time. Small animal believed to be a fox, however some attribute it to a long-tailed rabbit or a squirrel. I am leaning towards the rabbit. Similar example is found at Robert E. Haynes Catalog №3, April 9-11, 1982 on page 11, under № 15: “Rare design in style of Sanmai (three layers) / Wasei work. With yamagane core and heavy rim cover. The web plates are carved with double head Goto style waves and the face has a fox. The web plates were riveted at the seppadai.  See Lot 4, page 8. Ca. 1350. Ht. 6.6 cm, th. 3 mm” [underscore mine]. Quality of photo is so poor that I decided not to provide it here. The only difference betwen my tsuba and his is that his has a square hole on the right shoulder of the seppa-dai. Early Muromachi (if we follow Robert it is even Nanbokucho, 1337-1392) or Momoyama period. The Momoyama attribution is mostly based on a fact that “waves and rabbit” motif became most popular in Momoyama times. Mokkōgata tsuba of similar design in this collection - see TSU-0282.  

Iron tsuba of mokko form (quatrefoil) decorated with a pair of cherry blossoms (sakura) in small openwork (ko-sukashi) and inlaid in brass (suemon-zōgan) with designs of waves, distant pines, chrysanthemum flowers in halves, tendrils and leaves, lightning or thunder symbol (inazuma), flying geese and family chrests (mon): two interlocked rings (wachigai) on the face, and three encircled stripes (maru-no-uchi-ni-mitsuhikiryo) - kamon of the Kikkawa clan  - on the reverse. Hitsu-ana outlined with inlay of brass wire. Surface treated with lacquer. Copper sekigane. Though some consider this type of tsuba to resemble Heianjo school, “...the brass trim around the hitsu-ana is a characteristics of Ōnin work” [Japanese sword guards. Onin – Heianjo – Yoshiro. Gary D. Murtha. GDM Publications, 2016; p. 27.]. The Ōnin origin is reinforced by scattered ten-zōgan elements here and there through the plate. It is possible that the tsuba was initially of round form and later trimmed to mokko shape. Mid Muromachi period; 15th century. Dimensions: Height: 87.2 mm; Width: 87.9 mm; Thickness at seppa-dai: 3.6 mm.

Iron tsuba of round form with design of butterfly (left) and dragonfly (right) in openwork (sukashi), outlined with brass wire. Thin plate also decorated with five concentric circular rows of brass dots (nail heads) in ten-zōgan; brass wire outlines of the center of the plate. School: Ōnin ten-zogan. Late Muromachi period, 16th century. Diameter: 88 mm, thickness at seppa-dai: 3.1 mm. Another tsuba of similar design, Tōshō school, is illustrated in this collection; see TSU-0353. Reference to the design has been found at "Japanese Swords and Tsuba from the Professor A. Z. Freeman and the Phyllis Sharpe Memorial collections". Sotheby's, London, Thursday 10 April 1997; p. 18, item 37: "pierced with two large formalised butterflies...".