The supracrustal sequence at Garpenberg, south central Sweden, consists mainly of felsic gneisses with subordinate intercalations of amphibolites and stratabound sulfide and iron deposits. During the Svecokarelian orogeny this sequence was isoclinally folded, metamorphosed and intruded by synorogenic granitoids. The history of these supracrustals is characterized by at least two successive stages of metamorphism, followed by a stage of alteration at low temperature and pressure. A first stage (M1) of regional, low pressure, deformative metamorphism in the amphibolite facies was followed by retrogressive, low pressure, non-deformative metamorphism in the greenschist facies (M2). M1is considered to be related to the Svecokarelian orogeny, whereas M2represents a late or post Svecokarelian event. Later low temperature, low pressure, alteration is represented by cross-cutting fractures filled with mineral assemblages such as prehnite-epidote-calcite or chloriteprehnite. Petrologic and mineralogic evidence supports a metamorphic temperature for M1of ca 550°C and a total pressure lower than 3.5 kbar.