So I just learned about the "Ioun stone of Intellect".
In action, it is described as:
When you use an action to toss one of these stones into the air, the stone orbits your head at a distance of 1d3 feet and confers a benefit to you.
A number, potentially a larger one, of years ago I read Zelazny's works about Corwin and Merlin. In them a character from the Courts of Chaos, Mandor, has magic centered around these balls that orbit and do stuff. He shows up in Knight of Shadows and Prince of Chaos.
To what degree are the Ioun stones derived from Mandor's magic in Amber?
Variations on this, that would count as valid answers, can include:
- Are there defining differences in how they work or what they do?
- Are there competing sources, where some spheroid orbits one's head and gives powers, that predate Zelazny?