
Overview. The ceramic ring magnet is held up by a
3/8-inch diameter, 24 threads per
inch, threaded rod inserted in a cork that is pushed snug into the center
of the magnet.

The composite "floater" consists of
nine 3/32-inch cube magnets arranged in a grid pattern.
($0.15 each from
Wondermagnets, #0049)
N S N
S N S
N S N
Above them 6mm X 6mm piece of metal from a an anti-theft tag (the plastic-enclosed devices used to prevent items from being taken from a store). Above that is a 21 mm-long steel screw with another small cube magnet at the very top. This structure is held together magnetically.
In the background is a 1-inch diameter graphite planchet embedded in plaster. (Planchets are $8.00 for package of ten from Ted Pella, Inc.)
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