Raku-yaki is the most luxurius material used for the tea ceremony in Japan. The preparation of this unique ceramic requires an ancient technique that was developed only for matcha bowls, in Kyoto, about 400 years ago.
Today Raku-Yaki is still made in the same traditional way and it is often an object of envy for people who learn the tea ceremony. There are two main kinds of Raku-yaki: Kuro-raku which means black Raku-yaki, and Aka-raku, which means red Raku-yaki. This matcha bowl is black, so it is known as Kuro-raku.
A very fascinating feature of Raku-yaki is that it feels very soft and warm to the touch of hands or mouth. Though Raku-yaki is thick, it is very light, and given thick coats of glaze. This helps to give Raku-yaki its soft and warm material feel. It is created by heating for a shorter time with a lower temperature than any other general ceramics. (1,100C to 1,200C (2,012F to 2.192F) and about 10 minutes) It is said that the Kuro-raku's black colour brings matcha's bright green colour out into prominence.
Raku Yaki has a water-absorbing property, so it is possible for the ceramic to retain and "sweat" small amounts of water. In Japan the use of Raku-yaki is known to create an atmosphere Wabi-Sabi.
Wabi-Sabi is a Japanese aesthetic and spiritual ideal that implies authentic simplicity and imperfect beauty. In fact, each bowl is carefully Handmade, which means that the size and shape of each item can vary a little.