The iron is an excellent black colour with rich purple under tones and well forged with some fine surface texture. The iron is also smooth and in excellent condition. There are fine soft elongated tekkotsu in the mimi. There are obvious hitsu though the left side of the seppa looks to be shaved slightly and I suspect this is to accomodate a kozuka. There is a slight tapering in the thickness which is common in the earlier sukashi tsuba of Owari and also Kyo Sukashi.
The broad mimi (rim) and sparse geometric design are classic elements of Owari design. Add to that the typical tall squarish seppa dai and the gentle tekkotsu in the mimi and you have classic elements of Owari sukashi.
The design is described by the NBTHK as Itomaki sukashi tsuba 糸巻透鍔 or a Spool design. The Itomaki was a spindle used to hold silk for the purpose of weaving. The Itomaki was a very common design used throughout the Momoyama and do periods. The book Sukashi Tsuba (透かし鍔) published by The Sano Art Museum (佐野美術館)in Mishima has an almost identicle guard that is described as Matsuba SUkashi Tsuba 松葉透鍔 or pine needles and attributed also to the 16th – 17th century (Momoyama or Edo period). I can see both designs in this guard. The curviture of the design may lend itself more to the Matsuba design to my eye but of course either could be correct.
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