Raku pottery technique originates from Japan and is characterized by low firing temperatures (900°-1000°C) and the removal of pieces from the kiln while still glowing hot. These are then reduced into easily combustible materials which blacken the crackles in the glaze and the naked clay body.
Alpine clay is a very young clay, which forms out of the decomposition of the bedrock. This young clay is hardly plastic, because plasticity develops over time. However, it bears thermal shock well and is ideal for raku.
I always looked for a product which is as local as possible. In Japan, each potter’s village works with its own local clay type and out of its particularity and difficulties are born local pottery expressions. It is this close relationship to the surrounding land which I am looking for in my work.
To look for clay in the mountains is like a treasure quest. Finding it is a rare present since the fine particles are generally all washed down the steep mountain slopes and settle much further in the plains. Sometimes you happen to find a puddle on a mountain road or in a dip. Walking in the mountains or looking for the yaks on their summer mountain pastures, I find a small amount of clay which I bring home in my backpack.
At home the clay is dried in the sun, weighted, made into a watery slip and mixed with a slip of ball clay (which is very plastic) at a ratio of about 3:1. The liquid is left in the barrel to settle and some weeks later it is poured in a wire basket covered with cloth and left to stiffen. Once it develops the right consistency, it is stored in the cellar until it will be used.