Called Chinese puzzle balls, mystery balls, or generation balls, they are hard to find any info about on the net. Every link seems to be trying to sell me one. The most informative site has this to say:
The layers of the ball can symbolize different things. For example, four layers represent the four compass directions or the four basic elements: air, water, earth and fire. The carvings on the surface also represent or symbolize different things. Two of the most common figures presented on the balls are the dragon and the phoenix, which correspond to our yin (female) and yang (male) characteristics. The dragon represents an emperor, or the husband, and the phoenix represents an empress or the wife. A puzzle ball decorated with these figures symbolizes a happy marriage blessed with success and prosperity.This site says the number of concentric spheres equals the generations in the carver's family.
I think I'm going to have to call dibs on making a Wizard's "Tower" exist in a floating version of one of these puppies. Okay, not, really, you design it I'll be happy to use it.
Get the alignment just right just to open the front portal.
They could work as a nice treasure item container too, holding a saint's tooth, for instance.