The term ‘Yoshiro Mon Tsuba’ seems to have become a generic term to describe iron tsuba inlaid with brass sukashi mon (crests, badges) and no longer seems to refer to the famous master of the school, Koike Yoshiro Naomasa, who lived in the third quarter of the 16th century. I am not a great admirer of brass inlay tsuba (preferring gold, silver, etc), but have been fortunate to have acquired some examples of brass inlay amongst job lots at recent auctions. I thought that I would share some observations on my latest purchase, catalogued as ‘Kaga Yoshiro’.
The iron base of the tsuba is eight-lobed, rather than the normal round shape (8.0 cm high, 8.0 cm wide, 0.4cm thick) with a background inlay of water weed (with the usual loss of some of the inlay, less than 10%, which, as I have previously posted, I put down to galvanic corrosion). There are eight brass sukashi mon inlays, each inside a brass ring and the tsuba has the normal pair of kogai-kodzuka hitsu ana, also rimmed with brass. Like most Yoshiro tsuba it is unsigned (mumei). Trawling through various websites, books and old sale catalogues, I noticed two unusual features about this particular tsuba, namely the shape and method of inlay.
Out of 21 tsuba that I located, 18 of them were round, one slightly rectangular with rounded corners, one mokko and one cruciform (signed Koike Yoshiro). No other tsuba had the 8-lobed shape of this one. I think that Yoshiro tsuba were made primarily in Kaga and Bizen provinces and signed examples that I found were inscribed ‘Koike Yoshiro’, ‘Goto Hashichiro’, ‘Hirata Doden’, ‘Saburota’ of Bizen and ‘Saburodai’ of Bizen. The Goto signature (if genuine) indicating that this type of tsuba was also made elsewhere. I noticed that although most examples were labelled Kaga Yoshiro, some were Bizen Yoshiro. In general, those attributed to Bizen seemed to have more rectangular hitsu ana (is this a kantei point for attribution or did someone assign such a tsuba to Bizen and others just followed suit?) The only multi-lobed monsukashi tsuba I found were all iron. Sasano, #269, shows a 10-lobed example attributed to 1st generation Masashichi of the Hayashi school and another was attributed to Higo Hayashi Matahei. Is mine a rare example, representing less than 5% of an admittedly small population?
The other unusual feature is the sukashi mon inlay themselves. In my ignorance of tsuba inlay practices I had assumed that these tsuba were all made by hammering a slightly undersized piece of solid brass into the round holes in the iron plate resulting in a tight fit, polishing the surface flat and then piercing the sukashi mon design. This technique is described in the Nihon To Koza VI, page 21. Evidently this was done in most of the examples that I came across as the rim of the mon varies in thickness and is evidently part of the overall design (see example in Additional Information document).
One of the mon in my example (at the 2 o/clock position) is set slightly back from the surface of the brass rim at the front and stands proud at the back (less than 1 mm). Obviously the mon has been prepared separately and hammered into position with the brass ring around the hole having been inserted previously. The inlay has slipped or been put in sloppily. Evidence for this observation also appears in the joins in the brass rings, which can be seen in some of the inlay. To add further weight to this observation, I found a tsuba for sale in which the entire inlay mon appeared to had fallen out, or been removed, leaving just the brass rings. This tsuba had been awarded a NBTHK Hozon and was described as Kuyomonsukashi Mizumochirashizu ’, which I painfully translated from the Hozon as Kuyo-mon sukashi with scattered water weed, the Kuyo mon being the 9 luminaries or celestial bodies, the crest of the Hosokawa clan (the ninth being a larger central circle, not actually delineated in this or my tsuba, but presumably represented by the seppa dai). The Hozon certificate seems to identify the tsuba as mumei Heianjo, not Yoshiro. I thought that it strange that this tsuba was awarded a Hozon when the mon were missing, but I assume that the NBTHK decided that this was the original design. My tsuba has the same water weed design as this one, so is mine a Heianjo tsuba originally with the Hosokawa kamon that was converted to a Yoshiro design at a later time by hammering in the brass crests? A copy of the NBTHK certificate and Hosokawa kamon is in the Additional Information.
So what initially appeared to be just another standard Kaga Yoshiro tsuba has given me hours of investigative pleasure and raised a few questions.
A final question. The inner sides of the inlay are covered with verdigris (and brass polish?). Is it OK to clean the sukashi with a dental flossing brush to remove loose material, or should I leave alone as part of the age patina of the tsuba?
As always, comments on my observations welcome.
(Just a guy making observations, asking questions and trying to learn)