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A comparative study of selected geologic features from six classic districts, the Kokanee Range and Keno Hill, Canada; Coeur d'Alene, United States; Freiberg and the Harz Mountains, Germany; and Pibram, Czechoslovakia, demonstrates that silver-lead-zinc veins in clastic metasedimentary terranes form a distinct class of mineral deposits which can be typified by a descriptive model. These silver-lead-zinc veins have characteristic metal ratios and are comprised of galena, sphalerite, and a diverse suite of silver and sulfosalt minerals in a gangue of siderite, quartz, or calcite. The veins are typically enclosed by spatially restricted phyllic alteration. Silver-lead-zinc veins occur in various tectonic settings. The veins are hosted by monotonous sequences of clastic rocks intruded by gabbroic to granitic plutons and metamorphosed to at least the greenschist facies. The veins are late features in the tectonic evolution …