Ferrous sulfate

Used as a mordant and dye modifier, shifting many dyes darker. Sold by Alpha Chemicals on Amazon: https://www.amazon.com/dp/B007ODUI76?ref=nb_sb_ss_w_as-reorder_k1_1_7&=&crid=1BJL9Y8KL4ZM3&=&sprefix=ferrous.
First purchased June 1, 2025.

