So while the additional dissolved iron triggered an earlier-than-usual phytoplankton bloom, as the metal triggered growth in a greater number of phytoplankton cells, the bloom was only 15-20% larger than normal because the growth was limited by the amount of available nitrogen, another vital ingredient required for the organisms to develop.

BBC: Iceland volcano ash cloud triggers plankton bloom

Iron minerals take up dissolved nutrients and carry them to the seafloor, where they eventually become preserved in rock.

MSN: What green rust did long ago to the big blue ocean

Like other iron minerals, green rust readily absorbs dissolved elements onto its surface, but green rust is not only particularly efficient at this in many cases, it can also react with toxic dissolved trace metals to make them insoluble, and as a result, renders them in nontoxic forms.

MSN: What green rust did long ago to the big blue ocean