The University of Tennessee commission illustrates this process. The architect found a mobile on my site, and requested that I send this 18" diameter model made as a prototype for another job to them. Discussions followed to determine the materials: (stainless, and copper), the size (6 ft diameter), and added the shape of the outline of the African Continent, for the Black Cultural Center on the Knoxville, Tennessee campus.
This is the finished 6 foot diameter mobile. The structure is organized in a "nautilus" spiral: there is a small piece beginning at the inside, then larger elements added at right angles upward until the top shape is reached. As the mobile turns, it unwinds, and rewinds back on itself. The outline of the continent of Africa is burnished copper.