Ion-exchange reactions of alkali, base, and heavy metals on low-temperature oceanic hydrothermal rocks (LHRs) under equilibrium settings were studied. Depending on the major minerals, the sorptive activity of the association increases in the series (opal, quartz, hematite) ≪ (ferrihydrite < nontronite) ≪ birnessite. The exchange capacity of the first three minerals for base, heavy, and alkali metals does not exceed 0.10 and 0.25 mg-equiv/g, respectively. For ferrihydrite and nontronite, the highest achieved capacities (mg-equiv/g) were ∼1.50 for Mo; 0.60 for Cu and Pb; and 1.16-1.26 for Cu, Ni, Cd, and Pb. Birnessite has well-defined sorptive properties. Among the minerals studied, birnessite is characterized by the highest exchange capacity of 2.4-4.26 mg-equiv/g for the entire spectrum of the metals studied, especially for base and heavy metals. Heavy metals are sorbed on birnessite in above-equivalent amounts relative to the exchangeable cations of the mineral.