Helen Shupla is famous for her carved pottery as well as her exceptional melon jars.  This is one of her few black-on-black painted pieces.  The plate is fully polished and has an avanyu (water serpent) painted as the design.  Note the head of the avanyu is in the lower left of the photo.  The avanyu has a more stylized appearance on this piece.  The intricate painting is a striking contrast to the highly polished surface. It is signed on the back in the clay.  It is in very good condition with no chips, cracks, restoration or repair.