Tamamushi Tanto (玉虫) – Jewel Beetle

Tamamushi (玉虫): the iridescent jewel beetle

The tamamushi is a Japanese beetle whose shell blazes with shifting reflections of green, blue and gold. So precious was it that in the seventh century, thousands of its wings were used to adorn the celebrated portable shrine known as the Tamamushi no Zushi, preserved to this day at Hōryū-ji temple. It has long been a symbol of beauty, good fortune and prosperity.

This tanto carries those colours on its saya: a deep black lacquer alive with touches of green, blue and gold, shifting with every change of light.

A mirror-polished 1045 carbon steel blade with bo-hi

The blade is crafted in 1045 carbon steel, a robust and widely used high-carbon alloy that is straightforward to maintain. It follows a shinogi-zukuri geometry with a compact ko-kissaki tip, and is grooved with a bo-hi.

The surface is mirror-polished, with a broad, pale undulating line running along the edge. This gunome-style line is a decorative hamon achieved through chemical treatment, not through differential hardening: it faithfully reproduces the appearance of a traditional hamon without its metallurgical properties.

A buke-zukuri mounting with black dragons

The kawari-gata tsuba, nearly circular in form, is crafted from polished blackened ferrous alloy. It is pierced (sukashi) and sculpted with dragons in relief (takabori) across its entire circumference, finished with a rounded rim (maru-mimi). Two gilded brass seppa with serrated edges frame it on either side.

The fuchi and kashira in polished blackened alloy are smooth and unadorned. The handle combines a wooden core with faux green rayskin, bound in a black tsuka-ito hineri-maki wrap, with black menuki. The ichimai habaki in gilded copper-toned alloy bears a dragon in relief.

A black saya with flashes of green, blue and gold

The saya is crafted from solid wood, covered in a brilliant black kawari-nuri lacquer with iridescent flashes of green, blue and gold. The koiguchi is finished in glossy black lacquered wood with no metal fittings, whilst the rounded maru kojiri continues the iridescent motif. The domed black lacquered kurikata, fitted with a gilded shitodome, holds a black cotton sageo.

Dimensions and handling of the tanto

With a blade of 33 cm and an overall length of 55 cm, Tamamushi is a tanto of generous proportions. Its 17 cm handle sits firmly in one hand, whilst the overall weight of 0.7 kg keeps it light and responsive. At 57 cm in its saya, it is a format that showcases its iridescent reflections beautifully on a display stand.