Dear Mr. Pdah,

given the measurements refer to the magnetic susceptibility you have to deal with different types of magnetism.  The magnetic susceptibility depends on the minerals in which the iron is contained (Hrouda et al., 2009). The majority of minerals which do not accommodate iron in their lattice are diamagnetic yielding a negative moderate susceptibility, e.g., calcite and quartz. By contrast, Fe-bearing paramagnetic minerals give a positive read-out which can be higher by several orders of magnitude than those obtained for diamagnetic minerals, e.g., siderite. The  ferrimagnetic, which are most well-known  are magnetite [Fe3O4], maghemite [γ-Fe2O3], ferroxyhyte [δ-FeOOH] and pyrrhotite [Fe7S8].  Beforehand this issue needs some clarification. Based upon the type and magnitude of magnetic susceptibility you can get an answer whether you have to deal with heavy minerals, metasomatic minerals or anything else. At the moment we are still pocking in the fog.

Best regards

H.G.Dill

Question may be more clarified, is it OK?

Hello Mr.Dill and Mr.Ahmad! I wanted to ask a very simple question. Let me put the same question in another way.

How can a metapelite rock grow crystals of around 1cm magnetite through out the rock? These metapelites were encountered near the margins of the Sung Valley Ultramafic Alkaline Carbonatite complex. Is it due to contact metamorphism or something else? How can such a rock develop the magnetic porphyroblast?

Best wishes. Dame.

Large magnetite crystals could grew during metamorphism, but not in real metapelites. They more probably grow in meta-Ultrabasic rocks, say talc schist, pyrophyllite-schist etc. The question is are you sure that they are real-metapelites?