Mokume-gane

Mokume-gane (木目金, Mokumegane^?) is a Japanese metalworking procedure which produces a mixed-metal laminate with distinctive layered patterns. Mokume gane translates closely to "wood grain metal" or "wood eye metal", describing the way the metal takes on the appearance of natural wood grain.

Mokume-gane has been used to create many artistic objects. Though the technique was first created to decorate swords, the art survives today mostly in the form of jewelry and hollowware.

Mokume-gane is a product made by fusing several layers of different coloured precious metals together to form a sandwich of alloys called a billet. The billet is then manipulated in such a way that a pattern resembling wood grain emerges over the surface.

There are many ways of working the mokume metal to create different patterns. Once the metal has been rolled in to sheet metal or bar, several techniques are used to produce a variety of effects.

First made in 17th-century Japan, mokume-gane was used only for swords. As the traditional samurai sword stopped serving as a weapon and became largely a status symbol, a demand arose for elaborate decorative handles and sheaths.

To meet this demand, Denbei Shoami (1651–1728), a master metalworker from Akita prefecture, first came up with the process for creating mokume-gane. He initially called his product guri bori for its simplest form's resemblance to guri, a type of carved lacquerwork with alternating layers of red and black. Other historical names for it were kasumi-uchi (cloud metal), itame-gane (wood-grain metal), and yosefuki.

The traditional components were relatively soft metallic elements and alloys (gold, copper, silver, shakudō, shibuichi, and kuromido) which would form liquid phase diffusion bonds with one another without completely melting. This was useful in the traditional techniques of fusing and soldering the layers together.

Over time, the practice of making mokume-gane faded. The katana industry dried up in the late 1800s when the traditional caste system dissolved and people were no longer able to carry their swords in public. The few metalsmiths who practiced in mokume transferred their skills to create other objects.

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