At a weekend playdate for the girls, Jonathan showed me this movie:

It’s a ferrofluid sculpture by Sachiko Kodama, Yasushi Miyajima, Morpho Towers — Two Standing Spirals, higher quality clip at the link.

Another video, possibly showing a prototype and scale of the above fountain:

A ferrofluid is:

Ferrofluids are composed of nanoscale ferromagnetic particles suspended in a carrier fluid, usually an organic solvent or water. The ferromagnetic nano-particles are coated with a surfactant to prevent their agglomeration (due to van der Waals and magnetic forces).

In English, I think that means very small metal particles are coated with oil, then those oil-coated particles are suspended in another liquid. Sort of like a thin version of artists oil paint. A ferrofluid isn’t a liquid metal, it’s a liquid with lots of very tiny pieces of metal suspended in it. Sort of like a stable mixture of iron filings and oil. Ferrofluids do not retain any magnetism.

Ferrofluids can be made at home using water based or oil based recipes. It can also be purchased online (prices seem to run $12 to $25 per ounce).

Here’s someone playing around with ferrofluid at home using a bolt (instead of precision crafted metal spirals). The first 30 seconds are still images then it switches to video. Please jump around, the results are beautiful and fascinating, but it’s ultimately just 10 minutes of someone dripping liquid onto a bolt:

As beautiful as the spikey ferrofluid demonstrations are, this video shows patterns I would never have expected to see coming from magnetic fields:

The changing patterns looking like typographic ornaments or petroglyphs or cartoon drawings of bacteria. As pointed out in the YouTube comments, the pattern-transformation at 2:04 is especially crazy.

Most of the recipes online involve some scary chemicals.* However this video deserves linking not because it makes a ferrofluid from laser toner and motor oil, but because the guy has a spoon in his drill:

Yeah the music’s horrible. I’m surprised the magnets in the drill’s motor didn’t cause the stuff to shoot off the plate.

Someone needs to find a way to turn this into a sub-$40 desk toy. Way better than a lava lamp. If anyone’s interested in organizing production of something like that, I have sketches and ideas ready to go.

* Almost all chemicals scare me. I never had much chemistry in high school, don’t have anyone to ask and the margin of error seems to involve the range of explode->not-explode or horrible-disfiguring-chemical-burns->no-reaction. As someone who tends to learn by trial and error, chemistry is an area I actively steer my curiosity away from.