Image: Chicory Roots
We are not an expert on brewing coffee with chicory root powder, but we reckon it’s probably due to the physics of it. It simply means that ground coffee is denser than water but ground chicory root is less dense.
Even minor differences in density can make an object float or sink in water. For example, ice, which is just water, is only 9% less dense than water, enabling it to float on water.