The Meliata high-pressure unit, exposed in the southern part of the Western Carpathians, consists of four groups of rocks, which are characterized by different lithologies and metamorphic histories. (1) The most common are Triassic marbles, intercalated with metabasalts and glaucophane-bearing phyllites. Phengite from metabasalts and phyllites record KAr and 40 Ar 39 Ar plateau ages of 152–155 Ma which are interpreted to date the high-pressure metamorphism. (2) Blueschist-facies mafic rocks and subordinate glaucophane-bearing micaschists, devoid of marbles which contain relic low-Si muscovite and newly formed high-Si phengite; the 40 Ar 39 Ar data obtained for the micas indicate Palaeozoic ages of ≥375–380 Ma for the early amphibolite-facies muscovite and a ≤250 Ma age for the secondary blueschist-facies phengite. (3) Glaucophane-free phyllites and phengite quartzite with low-Si and high-Si micas, respectively; textural features indicate a polyphase evolution characterized by a greenschist-facies metamorphism followed by a blueschist-facies overprint; the high-Si micas provide evidence for an early Middle Jurassic age (172 Ma) of the high-pressure metamorphism. (4) Amphibolite-facies slices and blocks, overprinted by blueschist-facies metamorphism, represent old basement rocks. Regarding the differences in lithologies, metamorphic conditions and radiometric ages of high-pressure micas (older age for continental vs. younger age for oceanic rocks), subduction of a continental wedge prior to that of oceanic crust can be assumed. This interpretation is based also on palaeogeographical reconstruction of the Mesozoic Western Tethys between the Apulian promontory and the Tisza-Bihor continental block.