[meteorite-list] Tokyo magnetic dust after rain 14MAR2013

[drtanuki]

Dear List,
  We had rain 13/14 MAR 2013.  On the early morning of 14th I went outside and noticed an unusually large amount of black/brown magnetic dust in the rain pools on concrete and have collected it.  I don{t know if it is volcanic related, industrial or run-of the-mill soil; but strange that this was accumulated after over 12 hours of heavy rain and within a 1-2 hour period just minutes ago.  Samples will be studied soon. It would be very interesting if this is not terrestrial.

Any thoughts?

Dirk Ross...Tokyo