PURPOSE: To improve operation properties while the plasticity of clay and the developing and adhesive properties of glazes or decorative earth are increased by adding the microbe producing viscous material and nutritive to the raw material for ceramic art.

CONSTITUTION: The clay with excellent property for ceramic art is diluted with sterilized distilled water and is heat-treated, and then the flat plate-culture medium of agar containing cane sugar and monosodium glutamate as main components is coated with said clay, thereby forming a single colony. Bacteria of the genus Bacillus are obtained by separating high viscous colonies in said colonies. Next, distilled water is mixed with the clay 1, and its pH is caused to be seven by agitation. After the sterilization of said material under high pressure, said bacteria-producing viscous material are added to the clay 1, and further the material in which monosodium glutamate is mixed with cane sugar, flesh extract and peptone is added to the clay as the nutrition for bacteria. After its maturity, moisture is evaporated and the material for ceramic art is obtained. Grazes are also matured by adding said nutritive and bacteria.