Was the first Grecian formula… Roman?
This is Sandra Tsing Loh with the Loh Down on Science.
When it came to coloring hair, Ancient Rome was startlingly advanced. Their recipe for hair dye combines lead, sulfide, and lime. This creates nanocrystals which grow not just INSIDE hair strands but in cells themselves, down the length of each hair shaft.
Philippe Walter of the French State Museum’s Center for Research and Restoration and a research team from L’Oreal studied these nanocrystals. Turns out, they’re composed of lead, which is black, turning the hair black too. Permanently.
Today, Silicon Valley loves nanotubes and nanocrystals for computer chips: they’re strong, conduct electricity, and 50,000 can fit in one human hair.
But even those Techies can’t make Hair in a Can! Oh Ronco! I miss the 90’s.
Reference: Walter, P., Welcomme, E., Hallégot, P., Zaluzec, N. J., Deeb, C., Castaing, J., Veyssière, P., Bréniaux, R., Lévêque, J. L., & Tsoucaris, G. (2006). Early use of PbS nanotechnology for an ancient hair dyeing formula. Nano letters, 6(10), 2215–2219. https://doi.org/10.1021/nl061493u