|MadSci Network: Engineering|
From the information you give about your experiment, it is nearly impossible to conclude something about its inner workings. Nevertheless, what you describe seems to be closely related to the so-called Levitron, a toy consisting of spinning top levitating above a permanent magnet. Much has been said and written about the physics of the levitron, and there is a lot of incorrect information around, so let me direct you to a place where a correct, albeit very technical explanation can be found: Levitron - spin stabilized magnetic levitation. There are also links to acceptable popularizations on this page, so it should help you get going.
Hope that helps,
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