I inquired on a physics forum if there was a way to charge pigments and run current like in electrophoresis to try to make the pigments react. I have some art made with alcohol ink where the pigments repelled and reacted to one another to form stunning natural patterns. It appears certain pigments attract and others repel one another chemically under certain conditions. I was able to reproduce the results. Anyway so I check with the physics forum people and they came up with using electromagnets and iron shavings. It has been done before You can see a sort of fingerprint of the field created. But more recently a scientist ran sound waves thru a metal plate covered in sand and the various notes form geometrical patterns. Its fascinating to see. There are youtube videos about it.
That's... interesting. I've been toying with a magnetic rail accelerator; it would be nice to visually see the fields. I wonder if that would be helpful for me.