Minerals of the tetrahedrite group and Bi-bearing sulfosalts and sulfides have been identified in different mineral associations in the polymetallic (Cu-Bi-Co-Ni-As) vein deposit at Baycheh-Bagh, Zanjan Province, NW Iran. The tetrahedrite group members span the complete compositional range from tetrahedrite to tennantite with Fe and less common Zn being the dominant divalent cation. Two generations of tetrahedrite group minerals can be distinguished recording changes in chemical as well as redox conditions of the mineralizing fluid. The first generation (Ia, Ib) includes tennantite-(Fe) succeeded by tetrahedrite-(Zn) to tennantite-(Fe) of variable intermediate composition. Bismuthian tennantite-(Fe) containing up to 1.17 apfu Bi represents the second generation (II) formed during the final hydrothermal stage. Bismuthian tennantite is characterized by primary growth zoning and slight Cu excess; the latter indicating an increase in the oxidation state of the fluid. The compositional variation and zoning of tetrahedrite group minerals reflect multiple pulses of hydrothermal solutions with varying As/Sb content. The significant substitution of Bi for (As + Sb) in the X site in generation II tennantite indicates higher activity of Bi in the late ore fluids. The late-stage Bi-rich assemblages also comprise emplectite, wittichenite, bismuthinite, aikinite and native bismuth. Luzonite is also found with these assemblages. These minerals mainly belong to the final stage of mineralization and formed between ∼200 and 300 °C.

在伊朗西北部赞詹省 Baycheh-Bagh 的多金属 (Cu-Bi-Co-Ni-As) 矿脉矿床中，已在不同的矿物组合中鉴定出四面体矿物群以及含铋的磺盐和硫化物。四面体晶石组成员涵盖从四面体晶石到 Tennantite 的完整组成范围，其中 Fe 和较不常见的 Zn 是主要的二价阳离子。可以区分两代四面体矿物，记录矿化流体的化学和氧化还原条件的变化。第一代 (Ia, Ib) 包括 Tennantite-(Fe)，继之以四面体-(Zn) 到 Tennantite-(Fe)，中间成分可变。Bismuthian Tennantite-(Fe) 含有高达 1.17 apfu Bi 代表在最终热液阶段形成的第二代 (II)。Bismuthian Tennantite 的特征是初级生长带和轻微的 Cu 过量；后者表明流体的氧化态增加。四面体矿物的成分变化和分带反映了具有不同 As/Sb 含量的热液溶液的多次脉冲。Bi 显着替代 (As + Sb)  II 代钛白云岩中的X位点表明晚矿流体中 Bi 的活性较高。后期富铋组合还包括锂辉石、白钨矿、铋锌矿、铝锌矿和天然铋。吕宋石也与这些组合一起被发现。这些矿物主要属于矿化的最后阶段，形成于 200 至 300 °C 之间。