This is a piece of "seihakuji" (celadon porcelain) by Tsukamoto Kaiji, a Living National Treasure, or from his kiln, Kaizangama. The delicate "karakusa-mon" (arabesque pattern) and "tsuru karakusa" (vine arabesque) are applied using the "youkoku" technique, which creates a relief-like pattern on the surface. I inherited this from my grandmother. I've enjoyed displaying it as a decorative plate rather than using it as tableware. I believe it is in good condition, but it is a used item, so please refrain from purchasing if you are concerned. Approximate dimensions are as follows: Diameter: Approximately 34.7cm, Height: Approximately 5cm