Iron tsuba of mokko form with slanting rays of light (shakoh) Christian motif (Jesuit's IHS symbol) in openwork (sukashi). Traditional description of this kind of design is called "tokei", or "clock gear". Owari school. Edo period.

Size: 83.4 x 83.1 x 4.4 mm

NTHK certified KANTEISHO ("Important Work").  In a custom wooden box. For information regarding shakoh tsuba see article 'Kirishitan Ikenie Tsuba by Fred Geyer at Kokusai Tosogu Kai; The 2nd International Convention & Exhibition, October 18-23, 2006, pp. 84-91.  

Kozuka with seven insects (fly, grasshopper, bee, butterfly, dragonfly, firefly, and cricket) and grass with dewdrops motif. Shakudō, flush gold inlay (hira-zōgan). 95.2 (H) x 13.7 mm (W). Mid Edo period (Late 17th - early 18th century, Genroku era 1688-1703). Unsigned. Kaga school. A look-a-like kozuka (with five insects) is illustrated at Japanese Sword Fittings. A descriptive catalogue of the Collection of G.H. Naunton, Esq., completed and illustrated by Henri L. Joly, - 1912 on plate XXIX, №691 [LIB-1389 in this Collection] with the following description at page 54: "Shakudō, inlaid with butterfly, dragon-fly, grasshopper, locust and another insect, gold." See also tsuba TSU-0211 in this collection:    

Shimizu-Jingo tsuba with a dragon and vajra (on reverse) motif. Unsigned. Possibly, 3rd or 4th master of Shimizu-Jingo family in Higo province. Iron. Low relief carving. Edo period, 1700's. Height: 75.4 mm, Width: 72.2 mm, Thickness at seppa-dai: 4.0 mm

Iron tsuba of round form with circular iron wire fastened to the surface with iron and brass staples (mukade-zōgan); brass ring about 2.5 mm wide along the rim with chisel marks. Design repeats on the reverse. Copper sekigane. Early Edo, 17th century. Size: Height: 83.3 mm; width 83.9 mm; thickness at seppa-dai: 4.5 mm. Weight 173.6 g. Design is thought to resemble a centipede. "Centipede-like inlay (mukade zogan) of alternating iron and brass staples produce an appearance that was particularly favored by Takeda Shingen (1521-1573), one of the most powerful warlords of his time. The centipede is sacred to Bishamon (God of War) and especially propitious for a warrior. Shingen type, 16^th century.” [The Peabody Museum collection of Japanese sword guards with selected pieces of sword furniture, by John D. Hamilton. Photographs by Mark Sexton. Salem, MA, 1975.] See also: http://varshavskycollection.com/shingen-tsuba/ SOLD

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.

Iron tsuba of round form with design of ginger and double diamonds (myoga-ni-nigaibishi) in openwork (sukashi), details carved in kebori technique. Slightly rounded square rim. Copper sekigane. Shoami school. Early Edo period: Late 17th century (Kanbun/Enppo era). Height: 80.1 mm. Width: 79.8 mm. Rim thickness: 5.0 mm. Center thickness: 4.7 mm. Provenance: Sasano Masayuki Collection, № 110.  

Iron tsuba of six-lobed (mutsu-mokkō-gata) form, with six wild boar's eye shape (inome) openings (sukashi). Hitsu-ana and the entire perimeter of tsuba have typical for this school raised rim. Lobes are decorated with landscape motifs in low relief carving (sukidashi-bori). On the obverse: A hut under a full moon, Shinto shrine gates (torii) with pines and a full moon, rocks, a large pine tree, and a temple (pagoda) surrounded by rocks and waves. On the reverse: waves, fishing boat, wild gees in flight under full moon, maple, hexagon (tortoiseshell, kikko) with a dot inside and a dot outside (inclusion/exclusion symbol), and chrysanthemum (the last two may be family crests, mon). Kamakura-bori school. Late Muromachi period (1514-1573). Height: 64.2 mm, width: 74.3 mm, Thickness at seppa-dai: 3.2 mm, at rim 2.6 mm. Weight: 62.8 g (light). NBTHK old green certificate №561: Tokubetsu Kicho  - "Extraordinary Work". A look-a-like tsuba can be found at the Compton Collection, part II, pp. 14-15, №17, though his tsuba is more massive (80 x 84 x 4 mm). NBTHK paper says that the motif is Hakkei (八景), i.e. "Eight Views," so several interpretations are possible (the original Chinese ones, Omi Hakkei, etc.).  However, most likely it is the 'Eight views of Omi' (近江八景  - 'Omi Hakkei'). Why the artist selected a 6-lobed form for depicting 8 views remains unclear, and thus we are in our right to raise the question whether the motif is indeed Hakkei. The term Omi hakkei (eight views of Omi) refers to painting or print sets which illustrate life on the shores of Lake Biwa in Omi (now Shiga Prefecture). The model for such paintings came from China, where, from the eleventh century onward, painters had produced eight views of the Hsiao and Hsiang lake areas of Hunan Province. The themes, which follow the original Chinese models, are: geese descending to land, returning fishing boats, clearing rain, a snow-covered evening landscape, the autumn moon, night rain, a temple bell at evening, and the glow of sunset. Japanese artists have also used the eight-theme approach for other parts of country - including cities - and applied it to subject matter other than landscapes. [Merrily Baird. Symbols of Japan. Thematic motifs in art and design. Rizzoli international publications, Inc., 2001, page 308-9]. Japan Encyclopedia by Louis Frédéric also mentions Omi Hakkei as "Eight landscapes of Omi", and states that this theme was often cited in poetry after 1500. It is likely that the tsuba in focus is designed under the influence of the theme popularity in the 16th century. The theme was effectively exploited by prominent ukiyo-e artists Suzuki Harunobu and Utagawa Hiroshige in the 18th and 19th century, respectively. These are the eight scenes of the theme (see Wikipedia):

• Returning sails at Yabase (矢橋の帰帆) - Yabase. Yabase is an old harbour on the east side of the lake. Near the Tokaido, it was used for a shortcut to Otsu by boat.
• Evening glow at Seta (勢多（瀬田）の夕照) - The Chinese Bridge at Seta. The long bridge across the Seta was used by the Tokaido. In the background the "Fuji of Omi", the Mikamiyama. It is just above 400 m, but indeed well visible.
• Autumn moon at Ishiyama (石山の秋月) - Ishiyama Temple. The Ishiyamadera was located on a hillside next to the Seta River. It got his name form the strange rocks on which it is built, partly on supporting beams. A hut at the upper end of the site allows a view of the lake, and the moon.
• Clear breeze at Awazu (粟津の晴嵐) - Awazuhara. Awazu is well known for its pine wood, Awazu-ga-hara.
• Evening bell at Miidera (三井晩鐘) - Mii-dera. Miidera temple was built in the 8th century. Its famous bell is one of the "Three bells of Japan", the other two being those at Byoodo-in, Uji and at Jingoji, Kyoto.
• Evening rain at Karasaki (唐崎の夜雨) - Karasaki Shrine. Karasaki is a small cape with a single large pine tree, a hitsu-matsu.
• Wild geese returning home at Katata (堅田の落雁) - Ukimido. Alighting geese cannot be seen always, however the little temple near Katata in the square hōkyō-style, detached from the lakeside, connected by a bridge. The first part of the name uki is the same as in Ukiyo-e, meaning floating. Midō means temple.
• Evening snow at Hira (比良の暮雪) - Hira Mountains. The Hira mountains on the west side of the lake experience the hard winter, when the winter monsoon brings much snow from the continent.

In any case, as a conservative, I say that it is a landscape motif and a late Muromachi period work, rather than Omi hakkei motif and a mid-Muromachi work.

Iron tsuba of round form with two overlapping triangles (uroko) motif  in openwork (sukashi). Triangle patterns usually associate with 'fish scale', mon of Hojo family (and others). Edo period or later.

Size: 71.4 x 70.2 x 5.2 mm.

An association with the Star of David is doubtful if not impossible.  

Iron tsuba of round form decorated with design of dragonfly in negative openwork (in-sukashi). It may be Ko-Tōshō (old Tōshō) or just Tōshō school, without a 'Ko'. Probably the dragonfly here is used as a family crest (mon). Muromachi period. Dimensions: Height: 95.0 mm. Width: 93.6 mm. Rim thickness: 2.1 mm. Center thickness: 2.3 mm. Nakago-ana: height = 30 mm, width = 7.8 mm. A dragonfly design is described by John W. Dower as following "During the period of feudal warfare, the dragonfly is reputed to have been am especially popular design applied to arrow quivers, and some warriors adopted it as a family crest. One reason for this was the insect's alternative names of katsu mushi and shogun mushi, both meaning 'victory insect'." Merrily Baird is even more talkative regarding the matter: "The dragonfly (tombo) in Japan is emblematic of martial success, as various names for the insect are homophones for words meaning "victory". The dragonfly is also auspicious because references in the Kojiki and Nihongi link it in both name and shape to the old kingdom of Yamato. This legacy has led to the use of dragonfly as an emblem on arrow quivers and as family crest. It also appears occasionally in conjunction with such imperial motifs as the chrysanthemum. Used in a context devoid of historical associations, the dragonfly is a seasonal symbol of late summer and early autumn." Dragonfly was an extremely often motif for the tsuba in all times, primarily in earlier times, before Tokugawa pacified the nation. The same motif is used on Ōnin tsuba in this collection:

Iron tsuba of slightly elongated round form decorated with design of melon flowers, vines, and leaves in brass flat inlay (hira-zōgan) on both sides. Slightly raised rim (mimi) carved in a way to simulate ring-shaped covering (fukurin). Kozuka hitsu-ana and kogai hitsu-ana both plugged with soft metal (tim or lead). Copper sekigane. Heianjō or Kaga School. Muromachi or Momoyama period, 16th century. Iron, hira-zōgan brass inlay. Round (maru gata) form, diameter 79 mm. Size: 80.3 x 78.4 mm; thickness at seppa-dai: 3.4 mm; at the middle: 3.8 mm; before the rim: 2.4 mm, rim: 2.8 mm. Note on design: though this design resembles family crests with oak and mulberry leaves, I believe it's  a melon flower [see Jeanne Allen. Designer's guide to Samurai Patterns. Chronicle Books, San Francisco, 1990, page 114, №130 "Melon Flowers": Note about the distribution of thickness (niku-oki): "this tsuba has toroid features, niku raises from the rim towards the centre but thins once more out when approaching the seppa-dai" [M. Sesko, "Handbook...", p. 48].