After extracting the 'meat'(kernel) from the shell of the Black Walnut, there is alot of debris(from the shell) mixed in with the precious 'meat'.
Previously, visually. . .I carefully removed 3-5 small slivers of shell from about 1/2 cup of Black Walnut 'meat'.
An old Cherokee trick is to place the 1/2 cup of Black Walnut 'meat' in a pot of warm water and the lighter 'meat' will rise to the surface while the heavier shell-slivers will sink. Works!
True, the shell-slivers were accompanied by the huge pieces of 'meat'. However, that was fine since we are looking at 2-3 really-really large kernels. Using a strainer I can easily remove all the light 'meat'(kernels).