Edo kiriko is cut glass from the city of Edo (present-day Tokyo). It is said to have been first produced in 1834 by Kagaya Kyūbei who owned a glass shop in Nihonbashi Ōtenma-chō in the centre of Edo.
In 1881, a glass-cutting engineer, Emmanuel Hauptmann, was invited from the United Kingdom to train a number of Japanese craftsmen in the latest glass-cutting technology and, thus, the tradition became embedded in the fabric of the city. Cutting and polishing techniques developed and the quality of Edo kiriko improved, reaching the height of its popularity in the early years of the 20th century.
The Edo kiriko manufacturing process consists of six main stages:
Blowing the coloured glass
A thin, coloured glass overlay is created followed by a clear inner surface layer. This method is called pokan after the sound made when removing the glass from the kiln.
Marking the design
A pattern is chosen and a grid is drawn using red iron oxide pigment. For the vertical lines, a bamboo stick is used as a guide, cut to the same width as the chosen pattern. The horizontal lines are marked using a paper cylinder divided into equal parts, which is inserted into the glass.
The basic outline of the pattern is cut on an iron grinding wheel while using a water-sand mixture as lubrication. Alternatively, a diamond wheel can be used.
Next, a fine sand or a diamond wheel is used to create the finer cuts of the design.
Polishing with a whetstone
Naturally occurring whetstones from Goto and Sasaguchi in Kyūshū are used to start the polishing process.
Polishing with a wooden wheel
The cut surfaces are further polished with water-soluble polishing powder and iron oxide. A bristle brush may be used for polishing finer patterns.
A number of patterns are common in edo kiriko design, including fish roe (nanako), hemp leave (asanoha), spider’s web (kumonosu), chrysanthemum (kiku) and hexagonal basket weave (rokkaku kagome) patterns. Each pattern carries a special meaning.
Edo kiriko was designated a ‘Tokyo Traditional Craft Industry’ in 1985 and a ‘National Traditional Craft’ in 2002.