A grain conveying apparatus and system for conveying and separating elements of a grain mixture of a first minimum size, such as cob pieces, and a second maximum size smaller than the first minimum size, such as grain or corn, including an upper passage having at least one aperture generally smaller than the cob pieces and larger than the grain or corn. As the grain mixture is conveyed through the upper passage, the cob pieces will pass across the apertures, and the grain or corn will pass through the apertures to the lower passage thereby separating the elements of the grain mixture as it is conveyed from a source bin to separate receiving bins.