PURPOSE: To obtain a gravitational force to pull up the mouth of a vase upward, under a state other than a standing state by a method wherein for a part which is lower than the center of the vase under a standing state, the surface area of the contour is extended and made thicker without adding other substance.

CONSTITUTION: In order to make the weight of a part lower than the center of a vase under a standing state larger than a conventional vase, the surface area of the contour 1 for the lower part is extended. Thus, without making it extremely thick, the weight becomes larger, and the shape can be made spherical as well. For the manufacture, the ratio of the surface areas of the contour 1 which are partitioned into the upper part and the lower part, and the ratio of the thicknesses are simply adjusted as the major activities. In this case, the weight of the part which is lower than the center of the vase under a standing state needs to be twice or more of the upper part, and it is necessary to form the vase according to this standard. The vase which is formed in this manner easily rolls by the gravitational force of the lower part, and returns to the original standing state because the vase is made into a spherical shape, even when the vase is forced to fall sideways from the standing state.