Technically these are correct, so lots of good guesses! It is a fragment of a Pre-Columbian pot found in our family garden about 70 years ago……overlooking Lake Butte Des Morts, WI. Very common find in our neighborhood. It is fired from a glacial red clay. The next door land was a burial ground dating back at least 2 millennia used by generations of succeeding tribes. I’ try to include a picture of the entire fragment but I’m still trying to learn the technique.