These ceramic bowls by Belgian designer Ilona Van den Bergh are slip-cast in perfect half-spheres and reshaped while still pliable to create one-off pieces (+ slideshow).

Van den Bergh creates the warped forms of the Moon bowls after she removes them from the plaster mould.

Each circular piece is worked by hand to shape a gentle indentation across the curved surface that is slightly different every time.

The deformed bowls are then fired to fix their final shape.

"The design is based on a circle: a perfectly closed, round line," said Van den Bergh. "It is one of the strongest shapes, known and used throughout the history of mankind, as powerful in its simplicity as the sun and the moon."

"But it was a challenge for me to work with this perfect shape," she continued. "So once I remove the clay from the plaster mould, I deform the bowl. I create for each object a new curve, a new route, a new life."

The thin-walled containers are coloured with different "engobes" – liquefied suspensions of clay particles in water – giving them a matt white, grey, brown, red, pink or orange finish.

The bowls are designed to be presented in large groups. "As a collection, the objects evoke an organic and dynamic feeling," Van den Bergh told Dezeen.

"They breathe an atmosphere of serenity," she said, "where shadow and light bring the collection to life, where lines and shapes conduct the rhythm, where purity and simplicity rule."

Available in three sizes, with diameters of 10, 15 and 25 centimetres, the bowls are available to purchase individually.