Fig. 6. Cumulative amounts of (a) Fe, (b) Zn, and (c) S leached from pyrite, sphalerite, and 95% pyrite–5% sphalerite mixtures either with or without calcite as a function of number of leaching steps in the flow-through experiment. Each value is the mean of two replicates. The standard error bar (two replicates) is not shown when its length is similar to or smaller than the size of the corresponding marker.