Serpentine minerals in natural samples are dominated by lizardite and antigorite. In spite of numerous lab-oratory experiments, the stabilityfields of these species remain poorly constrained. This paper presents pet-rological observations and the Raman spectroscopy and XRD analyses of natural serpentinites from theAlpine paleo-accretionary wedge. Serpentine varieties were identified from a range of metamorphic pressureand temperature conditions from sub-greenschist (Pb4 kbar, T~200–300 °C) to eclogite facies conditions(P>20 kbar, T>460 °C) along a subduction geothermal gradient. We use the observed mineral assemblagein natural serpentinite along with the Tmax estimated by Raman spectroscopy of the carbonaceous matterin associated metasediments to constrain the temperature of the lizardite to antigorite transition at highpressures. We show that below 300 °C, lizardite and locally chrysotile are the dominant species in themesh texture. Between 320 and 390 °C, lizardite is progressively replaced by antigorite at the grain bound-aries through dissolution–precipitation processes in the presence of SiO2enrichedfluids and in the cores ofthe lizardite mesh. Above 390 °C, under high-grade blueschist to eclogite facies conditions, antigorite is thesole stable serpentine mineral until the onset of secondary olivine crystallization at 460 °C