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Abstract The metamorphic iron ore of Egypt occurs in a number of localities distributed mainly in the Northern and Central Eastern Desert, namely Gebel El-Shayib, Gebel Semna, Wadi Kareim, Wadi El-Dabbah, Umm Ghamis,Umm Shaddad, Wadi Sitra, Wadi Urnm Nar and Gebel El-Hadid. I. Classification of the Ore Types The metamorphic iron ore of Gebel El-Hadid can be mineralogically classified according to the predominant ore minerals into three main types; a) magnetite ore, b) magnetite-hematite ore. and c) hematite ore. XRD, TR, DTA and AMS support the petrographical classification of the three ore types. Geological, mineralogical and geochemical results of each of these ore types are summarized as follows: a) The magnetite ore type: is found essentially in hills A and B and rarely detected in hill C. It is characterized by predominance of magnetite over other minerals. Hematite, goethite, pyrite, siderite and chalcopyrite are sometimes present. The gangue minerals are quartz, calcite, chlorite, biotite, epidote, plagioclase, dolomite, ankerite and apatite. Banded, lensoidal, colloform rim and vein replacement textures are present. Chemically the magnetite ore has highest average contents of Fe203 (50.7), PeO (10.76), A1203 (2.04), MgO ( 0.52), K20 (0.13) and Fet (43.85). The highest average content of FeO indicates that this ore consists principally of magnetite. Geochemical parameters show that this ore has maximum average contents of F (88.73), A (2.23) and M. (1.45) and minimum content of C (7.58), compared with the other ore types. This ore type has minimum oxidation degree (82) and as a result, it is less oxidized and poor in hematite. |