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Podiform chromitite is genetically and compositionally different from stratiform chromitite of the layered intrusions. Examples of stratiform chromitite have shown an apparent enrichment in the platinum group elements (PGE) and minerals (PGM). Although, PGE content of ophiolite podiforms is generally low, exceptional enrichment in some PGE have recently been reported in several places such as Spain, Italy and Cuba. PGE enrichment is sometimes accompanied with high Cr # and certain PGM. They may also be restricted to a certain stratigraphic level of the ophiolite complex.
Studies on chromitite ores and associated rocks of some ophiolites such as in China, Greece, and Cuba have shown an existence of PGM inclusions and other sulfides in chromite minerals and related rocks, which lead to attribute the enrichment to possible sulphur saturation.
The most northern part of the Semail ophiolite (UAE ophiolite) consists of numbers of chromite localities that had been mined in the last decade. They mostly occur in the upper mantle peridotites and are similar to those podiform chromitites found in most ophiolite complexes. However, detailed study of PGE and PGM and other sulfides of these chromite ores and related rocks have never been concluded so far. Investigation of chromites or chromitites and some associated rocks in this part of the Semail ophiolite shows three groups of chromite deposits that are relatively different in composition and stratigraphic levels. Their PGE content is generally low but can be discriminated. In addition, PGE on these chromite groups seems to follow the value of Cr # and detailed compositions, which is probably related to the type of the tectonic environment in which these bodies formed.
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