The shape of this bowl is informed by a Greek precedent, the phiale mesomphalos. Such ritual libation vessels are named for the central depression on the underside that rises up into the center, allowing the bowl to be held with the palm outstretched and the middle finger reaching into the depression. With its separately attached omphalos and low foot, this bowl clearly builds on the Greek model by favoring form over function.
For a closely related example, see A. Oliver, Jr., Silver for the Gods, 1977, p. 26-27, cat. no. 3.