The natural bog Fe ore was crushed, cleaned and modified with 5% by mass KOH or Na2CO3. The surface morphol. (SEM-EDS), metals content as well as the sp. surface area and porosity (low-temp. N-2 adsorption/desorption) of the obtained metals were detd. and compared with the properties of natural bog Fe ore. The presence of Fe, Si, Mn, K, O, C, Ca and Al was found in the natural ore. The sp. surface area of the KOH and Na2CO3-modified ores decreased significantly compared to the starting material.