Many common materials like wood, water, plants, animals, diamonds, fingers etc. are considered not to be magnetic but are in fact very slightly diamagnetic. Diamagnets repel, and are repelled by a strong magnetic field, and two of the strongest known diamagnetic materials are bismuth and graphite. Compared to the forces created by traditional magnets, diamagnetic forces are exponentially weak, however when arranged and prepared properly, can produce startling effects, levitation in this case. UCLA university has done multiple studies and found the most efficient and effective configurations for showing levitation in action.
In the first configuration here we can see what seems to be a small golden cylinder floating in between two fingers. However in reality the magnet is levitated by a vertical superconducting solenoid electromagnet at a point at which the magnet is rendered vertically stable and however unstable in the horizontal plane. Thus, the floating magnet wants to move off sideways, but is however, for this reason is lined with bismuth and therefore repels the magnet overcoming the horizontal instability and the result is stable levitation.
Another configuration is shown below. In this one, the magnet is suspended at a point far below the electromagnet where in this case it is vertically unstable and stable on the horizontal plane, unlike the example above. Diamagnetic plates are placed above and below to stabilize vertically. In the case above, human fingers were used as the diamagnetic plates to accomplish for real what magicians claim to do while only producing an illusion.