ABSTRACT
Chromite mineralisation in Saudi Arabia is restricted to the upper Proterozoic mafic-ultramafic ophiolitic rocks of the Arabian Shield. The host rocks are serpentinized dunite and/or harzburgite. Several types of chromite mineralisation are recognized, but they are mostly of the massive and leopard types in addition to chromitite layers. Ore microscopic studies indicate wide variations in size, form and texture of the chromites from the different types. Solid silicate inclusions are common as well as rare sulfide grains and few PGM inclusions. The chromite probably formed by initial crystal fractionation from a basaltic (picritic) melt followed by segregation and gravitational settling.
