The kiln burn effect on the surface gives a sculptural quality, moving the eye around the form, as if kissed by warm sunlight and shadow. The addition of mineral and rock particles (kaolin, silica, feldspar, mica, quartz mineral chips) adds textural and visual movement to each piece. Also, vitrification in the kiln of various additives like silica melt creating a glossy glaze that is not uniform, sometimes almost as if wind swept. Some Shigaraki (and Iga) pieces will even have chunks of ash clinging to the surface. Iga and Shigaraki ware is unglazed high fire, and exhibits a spectrum of natural ash glazes from fully melted Shizenyu (natural ash glaze), to a partially melted Haikaburi (ash-covered) matte glaze.
Generally, the various clays used tend to have more permeability and porosity than most, adding changes in texture and if used in kyusu, these porous clays will thicken teas steeped in them. With cups, plates, canisters, I think the primary effect is aesthetic - bringing an elegance of texture, touch, aroma, form, and movement to the experience of tea.
- Please share your pieces, would love to see other member examples of porous, textural, youhen kissed pieces from Japan.
A few examples from my collection:
Taisuke Shiraiwa's (b. 1985 Hokkaido) a student of Yohei Konishi, now working in his home town of Hokkaido. Taisuke’s undulating textured 'freckled' cup and yuzamashi (cooling vessel) originally inspired my curiosity into Shigaraki pieces, as well as other more porous and textured teaware. His cup is light as a feather, the rim is slightly curved out to reach the lips. Natural ash glaze is both Shizenyu and Haikaburi. A real pleasure to hold. Youhen effect is both inside and outside the cup, swirling around like a flame.
Jozan III (b. 1924 Tokoname) 80ml wood fired kyusu using somewhat porous clay that has added kaolin (?) chips throughout. Some mogake effect is on the underside. Youhen effect is more subtle with partial natural ash Shizenyu glaze and vitrification occurring over 60% of surface.
Kazuya Furutani (b. 1976 Shigarakicho) is the son of Michio Furutani (1946-2000), renowned Shigaraki potter, an important proponent of the anagama (wood-burning tunnel) kiln. Kazuya’s Iga clay cup is heavier thicker than Taisuke’s, retaining heat well. It’s about 50% glazed inside so the exposed clay area is absorbing some liquid if it sits inside for very long. Bi-doro (glass) green glass ash glaze is dripping in parts of cup inside and outside.
Jozan III (top) with Kazuya Furutani (l left) & Taisuke Shiraiwa (l right)
Kazuya Furutani (left) & Taisuke Shiraiwa (right)
Taisuke Shiraiwa 'freckled' cup and yuzamashi (w Taiske's tokoname red clay kyusu above)