Commercial flake grate available for further grinding and processes is available in three primary sizes. These sizes are -100-mesh, +100-mesh, and +50-mesh. Depending on the source and requirements other more âexoticâ cuts are available, but the above three are generally considered the workhorses of the industry. From these three feed stocks most other grades, from +32 mesh coarse flake to 3-micrometer powder, are made.