Shingen school (or style) tsuba of round form with an iron core of spoked-wheel shape, with its centre covered with a copper plate decorated with star-shaped punch marks. From this copper plate outward, the body is formed by brass and copper wire (flat and twisted) in a weave pattern. Both hitsu-ana are outlined in brass with a raised rim. Copper sekigane. Unsigned. Edo period, 18th century. SOLD   Height: 98.0 mm, Width: 97.4 mm, Thickness at seppa-dai: 6.0 mm. Weight: 290 g. NBTHK certificate №436696: 'Hozon' attestation. Citing "JAPANESE SWORD-MOUNTS IN THE COLLECTIONS OF FIELD MUSEUM" by Helen C. Gunsaulus, Assistant Curator of Japanese Ethnology. 61 plates. Berthold Laufer, Curator of Anthropology. Field Museum of Natural History, Publication 216, Anthropological Series, Volume XVI; Chicago, 1923; p.45: "An unusual group of tsuba popular in the late sixteenth century and afterwards is made up of those guards known as Shingen tsuba, a name which was derived from a sixteenth-century warrior, Takeda Shingen (Takeda Harunobu, 1521-73), who is said to have preferred this style of guard, as it combined strength and lightness. Under the category of "Shingen", four different types abd generally listed, though a fifth appears in the drawings in the Boston Catalogue of Okabe Kakuya "Japanese Sword Guards" (p. 21). It is square, that form which is said to have been used in Ashikaga days for scaling walls, the sword having been set up as a step. [...] The following descriptions include, however, the Shingen tsuba usually met with.

1. So-called Mukade ("centipede") tsuba are made of iron in which a centepede is inlaid in brass or copper wire. Mukade tsuba of Myōchin and Umetada warkmanship have been found with the inscription, "Made to the taste of Takeda Shingen".
2. There are those of solid iron, with need centers of brass, to the edges of which is affixed a weaving of brass and copper wires which is bound to the foundation disk by a rim, usually decorated simply.
3. Another type is of solid iron, bored at intervals and laced with braided or twisted wires of copper and brass.
4. The fourth type is a chrysanthemoid form, chiselled in open work and laced or woven tightly with copper and brass wire."

I believe that my tsuba [№ TSU-0338] belongs to the fourth type. However, this particular specimen does not conform with the description of Shingen tsuba as combining strength and lightness. Its weight is 290 g, which tells us that most probably it had purely decorative function (as most tsuba in Edo period). A somewhat similar design can be found at wikimedia. A look-a-like tsuba is illustrated at Compton Collection, Part II, p.p. 26-27, №54. It is dated ca. 1700. It was in a box with Sato Kanzan inscription, and had NBTHK certificate attesttion of 'Tokubetsu Kicho'. Price realized: $5,280.