ABSTRACT
Representative samples of karst type bauxites, bauxitic laterites and bauxitic clays of Greece were analyzed for major and trace elements. Also the mineralogical composition of these deposits was determined by a combination of microscopic, XRD and DTA examinations. The investigation by SEM and electron microprobe revealed the presence of fine grained chromite fragments, with a wide compositional variation. The Mg / (Mg+Fe+Mn+Zn) atomic ratio range from 0.06 to 0.60 and the Cr/ (Cr+Al) atomic ratio range from 0.37 to 0.89. Primary composition of these chromites indicate that they can be classified to the high-Al type. Chromite can be used as an important petrographic indicator since from ultramafic and mafic roks it is transferred to bauxites and it provides evidence for the contribution of basic – ultrabasic rocks to bauxites.
