Liquid Iron sand-tank

Let's Make Robots Project Ideas
1

Hi folks,
some have seen my DIY plotter and I mentioned building a sysiphus-like sand table.
I’ve now ordered some black Iron-powder. I want to mix it with white sand from a sandblaster and put it in a fish-tank. Then I’ll use an electric magnet from below to create some nice patterns. No metal ball rolling around, just some mysterious traces will appear in the sand…

I need some clear liqiud to mix up everything, but keep the iron powder from rusting.
Does anyone know of a clear oil or some transparent anti-rust additive for water?

Thanks fo reading
o_lampe

2

I just figured out, that it’s actually iron-oxid (FE3O4)I bought. I hope that means, it won’t rust any further and keep the water clear.

3

What a big fail…
I mixed sand and iron powder 1:1 in a glass tank with 2cm deep water. It turned deep black instantly and the iron powder built a sticky surface on the sand. I couldn’t create anything interesting by moving around strong Neodym magnets from below. Adding more sand didn’t help. Then tried to move a 10mm steelball around but it got stuck in the mud.
Will try sand in a dry environment with the same steel ball, wondering if it rolls better. (at all)

4

It’ll likely depend on the type of sand too (grain size). What’s the latest?