The little spots are caused by iron particles in the clay, usually removed with a magnet.
Influence of cellular functions by iron particles has not been reported yet.
However, research is still ongoing and nanoscale iron particles are not yet commonly used for treating ground contamination.
However, there is still no corroborating observational evidence for the existence of these iron particles.
As clouds of tiny iron particles settled, they would make the surface appear redder.
It might even be possible to insert the iron particles into specific types of cells by attaching them to cell surface markers.
The reacting gases adsorb onto "active sites" on the iron particles.
Hematite is formed by iron particles' reaction to oxygen in the atmosphere.
I also believe they are using polyphosphates that sequester the iron particles and leave the hair oily.
It would be spread as a cloud of iron particles in space.