Original paper
Mineralogy of the Niederschlema-Alberoda U - Se-polymetallic deposit, Erzgebirge, Germany. II: Hessite, Ag2Te, and native Te (?), the first tellurium minerals
Förster, H.J.
Neues Jahrbuch für Mineralogie - Abhandlungen Band 180 Heft 2 (2004), p. 101 - 113
published: Jul 9, 2004
DOI: 10.1127/0077-7757/2004/0180-0101
ArtNo. ESP154018002001, Price: 29.00 €
Abstract
Hessite, Ag2Te, and native tellurium (?) constitute two, previously unknown tellurium species within the complex mineral assemblage at Niederschlema-Alberoda, Erzgebirge, Germany. Hessite is always intimately associated with clausthalite and has a composition close to ideal stoichiometry. The mean empirical formula is (Ag1.98Sb0.01)1.99(Te0.96Se0.05)1.01. Paragenetic relations and thermodynamic data suggest that hessite crystallized in equilibrium with clausthalite, berzelianite, and tiemannite under conditions of almost identical, high fugacitities of Se2 and Te2, which very locally were approached in the main selenide stage of Jurassic age. Native tellurium (?) formed as replacement product of hessite. Niederschlema-Alberoda provides the first record of hessite from an uranium deposit worldwide. Hessite and native Te are the first tellurium minerals reported from the Erzgebirge metallogenic province.
Keywords
hessite • native tellurium • selenium and tellurium fugacities • uranium deposit • niederschlema-alberoda • erzgebirge • germany