Could you confirm or deny that you are using the word "nanoparticles" carefully? I think that the ferrous particles in ferrofluids are mere particles. They'd

Could you confirm or deny that you are using the word "nanoparticles" carefully? I think that the ferrous particles in ferrofluids are mere particles. They'd have to be very, very small to be classified as nano, and we've seen before that making particles of an ordinary material that small can change its properties, ala "transparent titanium dioxide".