>>8636918 lb

Smart dust is NOT dust. It is just tiny computers.

Black goo is basically iron filings, ground finely into actual dust, and mixed with an oily substance like kerosene. The most common kind of black goo is ferrofluid and you can make it yourself.

How To Make Ferrofluid

https://www.popsci.com/diy/article/2009-09/making-ferrofluids-work-you/

Google ferrofluid to find interesting videos about magnetic fields