The results of these experiments indicate that most of
the transition metals that could be substituted in the
octahedral site were retained in the solid phase when
jarosite reacts under oxic conditions, and with pH controlled
by the Fe3+ mineral precipitation reaction. Similar
results were obtained from a study investigating the
transformation of schwertmannite to jarosite and
goethite (Acero et al., 2006). In that work, the authors
demonstrated that trace elements Al, Cu and Pb
associated with the iron oxyhydroxide were sequestered
in the solid phase when jarosite and goethite formed
from alteration of schwertmannite, but a small fraction,
∼ 1 to 20%, of the total cations were subsequently
released to solution when jarosite reacted to goethite,
although the remainder stayed in the solid phase. This is
important for managing sites that have abundant jarosite,
such as acid sulfate soils, because it shows that
most of the potentially toxic trace metals that can substitute
in the crystal structure will remain immobile if the
sites are flooded.