A moon jar stands more than forty centimeters tall and swells almost as wide. Porcelain clay is fine and smooth, which gives the jar its soft white skin, but it has little strength while wet. Pulled outward into so wide a belly, it slumps under its own weight. No potter could throw one in a single piece.
So they threw two deep bowls, turned one over, and set it on the other. Slip, porcelain clay thinned with water, bonded the rims. The join was smoothed until the wall read as a single curve.
Then came the part no one controlled. The heaviest point of the jar is its middle, exactly where the halves meet. As the clay softened in the kiln, that weight pulled on the seam. Some jars leaned. Some kept a faint dimple at the waist.
None of this was treated as failure. In their own time these were working vessels, known plainly as daeho, "big jar". Nobody called them moon jars until the twentieth century, when a painter looked at one and saw the full moon. By then the uneven shape was the reason people loved them.
jars like this are made