A four-sided tube with a central cylindrical bore, this cong can be viewed in cross section as a thick circle within a square or in three dimensions as a rectilinear solid pierced by a cylindrical tube.The core is slightly taller than the flat walls, resulting in a circular collar and base. Unlike others, this cong only has four eyes on each surface, two small eyes and two eyes with oval circle separated by horizontal channel. the stone mottled and streaked with cloudy off-white 'calcified areas and dark brown veining. 4 inch H, 1.08 inch W