By Kyle Holzhueter
Editors note: This is a full-length, instructional article. It is the type of in-depth information that you will only find here at TLS.
Kyomigaki, also known as Otsumigaki, is a polished earthen-lime finish often used in entrance ways and stair wells, that is, anywhere a more durable finish is desired. In pre-industrial Japan, due to its energy intensive nature, hydrated lime was a valuable commodity and was used sparingly. Kyomigaki uses roughly the minimum amount of lime needed to polish an earthen plaster, which provides a more durable surface than mizugone or nori-tsuchi, other popular earth based Japanese finishes. The following describes the preparation and application of Kyomigaki. My gratitude to the Kyoto masters for sharing their tradition.
Preparation of Materials:
Haitsuchi Brown Coat
The material ratio is 1 : 1 : 0.4 of clay : fine straw fibers : hydrated lime.
A combination of native Kyoto soils, white clay and Juraku soil 1:1 to 3:1.
All clay is sifted through a 1.5mm sieve.
Fine Straw Fibers:
Mijin fine straw fibers are sifted through a 1mm screen. The powder that falls through the sieve is saved for Mizugone, a different finish, and not used for Kyomigaki’s Haitsuchi brown coat. If the straw fibers are rather large, they should be separated again with a 5mm sieve. The fibers that do not pass through the 5mm sieve are too large for Haitsuchi and should be saved for a different purpose. In other words, the fibers should be between 1-5mm in length.
Dry mix the Juraku soil and white soil and then mix with water.
The dry clay is mixed with water, and then the straw fibers are added. To ensure full saturation of the clay and straw fibers, this mix should sit hydrated for one week.
Clay mixed with fine straw fibers and allowed to ferment for one week. Due to the fine nature of the clay and fibers, this mixing trough of materials is valued at over $1000USD.
To reduce the cost, Hidashi straw fibers can be used in place of the fine mijin straw fibers. However, after the finish has completely dried, the outline of the Hidashi straw fibers in the sub-layer may be visible.