This setup uses two 'Sedona2' 6-inch long magnets mounted on machinist blocks
that are clamped on a 1/8-inch thick by .5" wide iron bar that is slightly
scooped toward the center along its upper surface. A Faber-Castel 1.4
mm-diameter pencil lead with a thin copper foil wrapped around it is
floating. The period of large amplitude vibrations was approximately 5
seconds.
Sedona2 refers to Dale Young's handle on Ebay when he sells magnets. The pair shown above are have 5" x .5" pole faces and are 0.2" thick. The minimum bid is $32.50 for two magnets.
This photo shows Meredith's current H-type design. The three magnets are
Sedona2 with 3" by 0.5" pole faces, 0.2" thick, with the same
pole on top for all three. The H is constructed of a thin mica square and
four strips cut from 'science
toy' pyrolytic graphite. Each magnet has a strip of iron
strapping material along its upper face. This iron strip significantly
increases the lift. The assembled H weighs about one gram and will still
levitate with an additional gram of added weight.