Harvesting common amaranth seeds

I figured common amaranth would have seeds just like the cultivated grain amaranths, since the plants look so much the same—but no. We harvested some the other day, and the seeds were like tiny black specks. I wasn't expecting them to be so small, neither did I expect them to be black (there's nothing wrong with black seeds; I just thought amaranth seeds were the same approximate color as the flower/seed heads). Interesting and cool, but viable as a practical pseudocereal? Maybe not. Definitely different from grain amaranths.