Abstract
An unusual association of Se minerals was studied. Se enters into the structures of sulphosalts - into bournonite, jamesonite and tintinaite at concentrations up to 0.10, 0.38 and 1.11 apfu, respectively. However, Se and Te, together with Bi, also form discrete minerals such as tetradymite, laitakarite, ikunolite and hedleyite. Members of the laitakarite-ikunolite solid solution display a wide range of anion substitution from the nearly Se-free (0.10 apfu) end member to the S-poor (0.42 apfu) end member. Their contents of Te are low. Accompanying tetrahedrite does not contain Se or Te.