Square hero showing a powder segregation test with two bottles filled via funnels, one fast and one slow, each cored for top-middle-bottom sampling.

A clean, square illustration of two clear bottles under funnels. One bottle fills quickly, forming a cone. The other fills slowly, forming layered bands. Both have a central sampling tube for top, middle, and bottom draws. The scene visualizes a simple powder segregation test used to spot percolation and trajectory sorting.