The combined scheme of thermal and atomic-absorption analyses with the use of synthetic minerals for calibration allowed development of a method for identification of lead species in solid mineral samples. It is shown that sorbed Pb can be reliably separated from its other species. Unlike Hg and Cd, determination of structurally bound (isomorphous) Pb is problematic because of the overlapping of peaks of its release with absorption peaks of Pb vaporized from its own mineral forms. Lead cannot enter the ZnS and CdS structures (≤∼10−5 wt.%) under hydrothermal synthesis of minerals at 400 °C and 100 MPa. In K-feldspar synthesized under excess Pb no more than 1/3 of total Pb content may occur as isomorphous admixture. It is confirmed that sorption of elements plays an important part in hydrothermal processes. Comparison of data on the heavy-metal system Hg-Cd-Pb shows that the temperature of release of an element correlates with its volatility and thermal stability of its particular species depending upon the bond strength of this element.

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