G'day. By heating the magnetic discs you probably destroyed their
I have suggestions; Firstly I am not too sure that haematite can
be magnetised; I have no personal experience of it; I just am not
sure. If they can be magnetised, thread the beads on a wire and
ensure that they are forced tightly together. Take a powerful
permanent magnet and pass it along the taut string several times in
one direction only. Bring a compass near the string to detect if
the beads have retained magnetism (a cheap toy compass is sufficient
as a detector)
They could be placed inside a long coil of wire and an electric
current momentarily passed through the coil, then tested with the
I have magnetised items by placing them between the poles of a
converted transformer - take out the U and I iron, remove the
secondary coil and place the irons back in the primary of the
transformer and apply a DC electric current across the leads for no
more than a second.
To demagnetise items such as screwdrivers, cassette tapes video
tapes, energise the coil with an AC current and slowly withdraw the
item from the magnetic field. I made a bulk tape eraser like that.
I used it in the days (long gone) of semi professional video tape
to wipe 8 inch diameter reels of 1 inch wide tape. But you have to
be quick and cut off the power before the wires start smoking!
I am sceptic about the efficacy of wearing magnetic bands to
relieve arthritis - and I suffer from that quite badly; it never
worked for me (neither did 8 sessions of acupuncture).
Cheers for now,
JohnB of Mapua, Nelson NZ