A-Hydrothermal Metasomatic deposits in carbonate and dolomitic rocks: Through this process mechanism, when hydrothermal solutions penetrate into the dolomitic rocks, because the ionic radius of calcium is about 36 % bigger than that of the Magnesium, these two elements therefore cannot replace one another isomorphically; however because the Iron ionic radius is not so much different from that of the Magnesium, a series of
isomorphic minerals like Magnesite, Hontite, Bronzitite and etc.