Geology and Geochemistry

World demand for magnesite has drastically increased and it is expected to rise further sharply within the present decade, because of its recent utilizations in Mg-metal industries and automotive components, as slag conditioner and an advance value-added material. The Kraubath-type magnesite deposits of Khuzdar district, Balochistan, Pakistan are hosted within the serpentinized harzburgite rocks, associated with Bela Ophiolite of Cretaceous age. Soon after their formation, the ultramafic rocks of Bela Ophiolite were subjected to intense alteration and low temperature metamorphism and as a result converted into antigorite-serpentinites beneath the mid oceanic ridge. Dissolution of the silicates in sea water, mainly provide Mg ions with little amount of Ca and Fe. Carbonation of these released ions promotes the formation of hydroxides and carbonates of Mg, Ca and Fe in different combinations. Most of them are unstable and finally they convert into stable magnesite phase. The studied magnesite deposits are medium in quality and quantity and is mainly used to produce Mg-metal, caustic, dead-burned and fused magnesia.