The Solea graben in the Troodos ophiolite of Cyprus is host to some of the largest and richest cupriferous sulphide deposits on the island. The graben is oriented in a northwesterly direction and defined by similarly oriented dykes and faults. The deposits within the graben display a variety of characteristics which reflect their mode of genesis. They include deposits displaying classic exhalative genesis, as well as others which formed at some depth below the seafloor, or by fluids which travelled away from their source to deposit sulphide on the surface of the ocean floor. A special case is the Phoenix deposit which is the result of supergene enrichment from the weathering of massive sulphide. A strong control of ore deposition is evident for some of the deposits by a major structure interpreted as an oceanic detachment fault. Other deposits are localised at the intersection between axial structures and transfer faults. However, in all cases, an underlying heat source appears to have played a major role in ore deposition. The location of the deposits at the top of the volcanic sequence is consistent with an off-axis setting.

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Cyprus sulphide deposits belong to the mafic type of Volcanogenic Massive Sulphide (VMS) deposits and are associated with the Troodos ophiolite which formed in a supra-subduction zone fore-arc setting around 91 ma. The deposits are commonly exhalative, and occur at various stratigraphic levels within the ophiolite from the top of the Upper Pillow Lavas to the top of the Sheeted Complex. Structures often play a controlling role in ore deposition; however, in some deposits the presence of structural control is obscure, and an underlying heat source may have been the primary driver of hydrothermal fluids. Alteration associated with the mineralisation is typified by feldspar-destruction, with quartz-chlorite growth, and removal of alkali elements from the inner parts of the ore zone and deposition in the periphery of the orebodies. As surface indications of mineralisation have been exhaustively explored, the search for concealed deposits must make effective use of their geophysical signature, coupled with techniques which are least affected by the conductive cover.

The deposits of Rio Tinto are located in the Spanish segment of the Iberian Pyrite Belt and are hosted within felsic porphyritic volcanic rocks and tuffs. The orebodies comprise a spectrum from sedimentary exhalative (San Antonio) to sub-sea floor replacement of the volcanic host rocks (Filon Norte); the two largest masses (San Dionisio and Filon Sur) are closely associated with black shale and probably formed by partial replacement of these units in an anoxic setting. Alteration associated with ore deposition is typified by marginal sericitic (white mica) alteration, and central chloritisation and silicification in a multi-phase alteration history. Structures formed during initial plate convergence may have acted as controls on ore deposition, and evidence of such controls is retained in the distribution of various elements in the sulphide deposits. Tectonism followed the mineralisation, and overprinted previous extensional events and resulted in the development of slaty cleavage in the pelitic rocks with partial remobilisation of sulphides, and tight folds with associated shearing of the southern limb.

The South Mathiatis deposit in the Troodos ophiolite of Cyprus is located within Lower Pillow Lavas in the central part of the Mitsero (Ayios Epiphanios) graben, and is characterised by elevated Zn contents, and a hydrothermal mineral assemblage in which galena is locally an important component and barite is a common gangue mineral, features which place it apart from other Cyprus-type deposits. The mineralisation is hosted within a gently dipping sheet flowdominated sequence of lavas with common autobrecciation textures and associated hyaloclastites, and is stratigraphically controlled between lava flows, locally floored by unmineralised hyaloclastites. The environment of extrusion is interpreted as a ponded sequence, similar to the adjacent Agrokipia deposit. The Zn-rich mineralisation appears to be controlled by local structures which allowed access to the hydrothermal fluids, which then migrated laterally along lithologically favourable concordant zones. The sulphide assemblage is dominated by sphalerite together with ubiquitous pyrite; however, both chalcopyrite and galena are locally important; quartz and barite comprise the gangue-mineral assemblage. Red jasper is spatially associated with the sulphide mineralisation and displays abundant filamentous structures similar to forms identified in other VMS environments. Wall rock alteration associated with the mineralisation is weak, and this is reflected in the absence of a magnetic signature, in contrast to typical Cyprus deposits. The Zn mineralisation is also transparent to electrical methods suggesting that other similar deposits may be present in the ophiolite but remain as yet undetected.