AbstractReaction textures are often used to derive pressure‐temperature‐time (P‐T‐t) paths for metamorphic rocks. However, because dry rocks in particular react very little unless P‐T changes are accompanied by deformation and/or fluid influx, it is possible that mineral assemblages and reaction textures in polycyclic rocks record segments of P‐T paths that are unrelated in time. Such a case is documented, by garnet Sm‐Nd chronology, for a mafic granulite with well‐developed two‐stage garnet breakdown textures from SøHstrene Island, Prydz Bay, Antarctica. The combined geothermobaro‐metric‐geochronological evidence shows that the garnet formed during M1 at ca. 1000 Ma, ca. 850–900°C and 10 kbar. The garnet breakdown reactions producing symplectites of (1) orthopyroxene and plagioclase and (2) orthopyroxene, plagioclase and spinel occurred, respectively, during post‐M1 decompression and during a second granulite facies metamorphic episode (M2), in response to heating and decompression at ca. 500 Ma, ca. 750°C and 6 kbar. The date for the latter event derives from a nearby garnet‐sillimanite gneiss and corresponds to garnet ages which provide evidence for a regional granulite episode extending further north‐east along Prydz Bay. These data demonstrate that, in the absence of reliable criteria for heating and cooling and without age constraints, reaction textures cannot be assumed to record pressure or temperature changes in a single thermo‐tectonic event. Preservation of the ca. 1000 Ma age of garnet in rocks that have been reheated to ca. 700–750°C indicates that the closure temperature for Sm and Nd in garnet is at least 100°C higher tha