Daruma is the Japanese pronunciation for Dharma the Hindu-Buddhist deity. He came to Japan to spread his philosophy and is considered the founder (or one of the founders) of Buddhism in this country.

But related to ceramic kilns the meaning is much more down to the earth.

He wanted to reach Illumination and with that purpose he seat down with the crossed legs to meditate. Nobody knows how long it took him to fulfill his objective, legend took care of this detail and it is said that it was so long his legs and arms became one whole thing with his body. At present it is represented in the shape of a snow-man-like with the eyes open.

Politicians keep a replicate with blank eyes for when the recount of votes is finished, if the result is positive they celebrate the victory first of all by painting in black the apple of his eyes. Thus meaning that “illumination” was reached.

The clay used to make these tiles is red, they are unglazed, their color is due a peculiar way of firing them: In the early process of cooling, water is introduced in the kiln thus producing an intense vapor which results in carbon deposited on the surface of the pieces. This is called “ibushi” firing and the tiles are also called “Ibushi tiles”.

The kiln below, extant in the Roof-tiles Museum of the Omihachiman city in Shiga Pref. shows two opposite openings: the combustible feeding mouths while the central one is used for stacking the kiln.

What has affected most its survival is that, recent experiences after frequent earthquakes have lead to the conclusion that roof tiles should be substituted for something lighter. Research with this objective is leading to the dosing of lighter clays impervious to water a “must” condition for a tile.

Yet, folklore and the well know love of Japanese for things traditional, keep them alive, albeit in very few places.

And in the way, Daruma kilns have been found useful for many other purposes.

Water reduction, at present, being a technique used also in raku-firing, is relatively popular among clay artists.

In Tokoname and in other teapot producing ceramic centers, unglazed teapots are also fired this way, and so are some tableware items related to the tea ceremony, to cite only a few examples.

Data kindly given to me through the Museum, from a tile producing tunnel kiln placed nearby:

Firing temperature is (usually) from 1060 to 1200˚ Celsius. The complete cycle include the cooling of the pieces to about 300˚ C in 24 hours. When cooling down, in between 800 to 600˚ C water & kerosene is introduced inside the firing chamber for a space of about 2 hours.

Notes: In my explanation I refrained from using the word reduction because carbonization is not reduction although the atmosphere is a reductive one. Or it is?

This misconception was cause of one of my failures: a few years ago, while looking for an interesting background for the painting of decorative tiles with the “cuerda seca” technique I learnt in Spain, I thought that for the vivid cuerda seca colors a silver grey background would be wonderfully looking. The result was disappointing because when firing (OF) the cuerda seca colors, the beautiful silver grey color was gone and the result was a dirty red, that is, the original color of the clay after an ordeal!

As a conclusion I had to look for colors that would resist carbonization and this lead or mislead me to the study of luster techniques. But this is another story I would like to comment on, any other time.