said by Raphion:
Aluminum, like any non-magnetic conductor, becomes temporarily magnetized in the presence of a changing or moving magnetic field, due to currents being induced within it. Maybe moving a magnet over the powder would temporarily magnetize them causing them to line up with one another.
You need a strong magnetic field and continuous aluminum to get an electromagnetic effect. Won't work with powder.
If the well wasn't so deep I wonder about contamination. Magnetite is used in toners (Xerox) , inks US currency, etc.
"Facts do not cease to exist because they are ignored." - Aldous Huxley
"When a true genius appears in the world, you may know him by this sign, that the dunces are all in confederacy against him." Jonathan Swift