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The Troodos ophiolite of Cyprus hosts chromite deposits both as podiform bodies within the basal harzburgite and as lesser layers and schlieren within the overlying dunites and clinopyroxene dunites of the metacumulate sequence. All chromitite types have been studied from both field and mineralogical aspects, with particular emphasis on the chemistry of the ubiquitous silicate inclusions within chromite grains. Two distinct inclusion assemblages have been documented. Chromites from podiform bodies contain abundant hornblende, serpentine, ortho-and clinopyroxene and lesser olivine, while those from the metacumulates host pargasite, albite, serpentine and rare pyroxenes. This implies that no single silicate inclusion assemblage in chromite can be considered typically ophiolitic. The presence of an alkalirich fluid phase during chromite crystallization as evidenced by the unusual mineralogy of these inclusions has already been widely discussed in the literature. However, the marked stratigraphic control of inclusion types in chromite as reported here enables more complete modelling of the evolution of this phase to be made.Theories regarding the origin of chromite deposits in ophiolite complexes have undergone a remarkable evolution in recent decades. Formerly, models proposed to explain the occurrence of chromitite within the basal sequences of ophiolites were essentially orthomagmatic, accepting that chromite crystallized from a silicate melt. While some workers (Dickey 1975;Greenbaum 1972Greenbaum , 1977 considered all ophiolitic chromitite bodies to represent early deformed cumulates, most recent models (Cassard et al. 1981;Lago et al. 1982) assume the formation of podiform chromitite in magmatic conduits crosscutting mantle peridotites.The recognition of a broad variety of inclusions within chromite grains, including hydrous and Na-and Ca-rich silicates, together with new data on the petrological evolution of the ultramafics, has led some workers (Johan et al. 1982(Johan et al. , 1983(Johan et al. , 1986) to stress the participation of a fluid phase in the formation ofchromitite concentrations. Yet while the existence of such a phase during chromite crystallization is now well established, both the origin of this phase and its exact role in the formation of chromite remain controversial.The main purpose of this paper is to present new data on the chromitite deposits of the Troodos ophiolite, particularly on the widespread and mineralogically complex suite of inclusions hosted by the chromite. While both solid (PGM, sulphide and silicate) and fluid inclusions have been studied in detail, this paper will concentrate on the mineralogy and petrological significance of the silicate inclusions. Other inclusion types are described in detail elsewhere. Geological settingThe Troodos ophiolite, occupying the south-central part of Cyprus (Fig. 1), forms part of the Tethyan belt of ophiolites which extends from Spain in the west to the Himalayas in the east. It is the westernmost of a group of ophiolites along the northern...