A descriptive model for silver-lead-zinc veins is constructed from a comparative study of selected geological features from six classical districts, the Kokanee Range and Keno Hill, Canada, Coeur d'Alene, U.S.A., Erzgebirge and the Harz, Germany, and Pribram, Czech Republic. Silver-lead-zinc veins consist of galena, sphalerite, and a diverse suite of minor sulfide, silver and sulphosalt minerals, in a gangue of siderite, quartz or calcite. Massive mineralization and sulfide-cemented breccia lenses occur along large brittle-ductile stuctures. Silver-lead-zinc veins have metal ratios distinct from those of other deposit-types. The veins are typically enclosed by spatially restricted phylic alteration. Silver-lead-zinc districts occur in various tectonic settings, hosted by monotonous sequences of clastic rocks intruded by gabbroic to granitic plutons, and metamorphosed from greenschist to granulite facies. The veins are late features in the tectonic evolution of an orogen and commonly occur near a crustal-scale fault.
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