Abstract: The present invention relates to the investigation of particle characteristics, particularly to a device for measuring the apparent density distribution of a set of particles composed of several subsets of particles with different apparent densities and able to implement a flotation process to measure this distribution and comprising a flotation container, a stirrer and a system for measuring the density of the liquids, characterized in that the inside wall of the container has at least a first part in the shape of an inverted cone with axis Y whose height is 1.5 to 3 times its maximum diameter, and in that it has means for extracting liquid communicating with said first part at the vertex of the inverted cone, said means having a tube communicating with said first part at the tip of the inverted cone of which the first axis makes an angle of between ?/2 and 3?/2 radians with the second axis.